The correct answer is both (A) and (R) are true and (R) is the correct explanation of (A).

Key Points

• Ajatasattu was a king of Magadha in ancient India during the 6th century BCE.
• He had ambitions of expanding his kingdom and consolidating his power.
• One of his targets was the confederacy of the Vajjian republics, known as the Vajjis.
• The Vajjis were a powerful and well-organized group of republics, and Ajatasattu saw them as a threat to his dominance.
• According to historical accounts, Ajatasattu was conflicted about whether to attack the Vajjis or not. 
• He had heard of the Buddha's wisdom and influence and wanted to seek his counsel on this matter. Therefore, Reason (R) is correct.
• However, Ajatasattu was concerned that if he approached the Buddha himself, his true intentions might be revealed, and the Buddha could advise against violence and warfare.
• To assess the Buddha's disposition and gather information, Ajatasattu decided to send his minister, Vassakara, as an emissary. Hence, Assertion (A) is correct.
• Vassakara was tasked with observing the Buddha closely and reporting back on his physical appearance, behavior, and teachings.
• Vassakara went to the Buddha and observed his serene demeanor and compassionate teachings.
• The Buddha's emphasis on non-violence, peace, and moral conduct made a profound impression on Vassakara.

• He returned to Ajatasattu and described the Buddha's wisdom and peaceful teachings, urging the king to reconsider his plans for attacking the Vajjis.

Based on the above discussion, we can conclude that both (A) and (R) are true and (R) is the correct explanation of (A).

The correct answer is Submarines.

In News 

• The sixth and last of the French Scorpene-class submarines, INS Vagsheer, was launched into water at the Mazagon Docks in Mumbai

Key Points

• The six submarines were being built under Project-75 by the Mazagon Docks under technology transfer from the Naval Group as part of a $3.75-billion deal signed in October 2005:
  • INS Kalvari was commissioned in December 2017;
  • INS Khanderi in September 2019;
  • INS Vagir in November 2020;
  • INS Karanj in March 2021; and
  • INS Vela in November 2021.
• P 75 is one of two lines of submarines, the other being P75I, as part of a plan approved in 1999 for indigenous submarine construction with technology taken from overseas firms.

The correct answer is Gujrat.

Key Points

• The Bardoli Satyagraha was launched in Gujrat province of British India.
• The leader of Bardoli Peasant satyagraha was Vallabhbhai Patel.
• What triggered the Bardoli Satyagraha was the erstwhile Bombay Presidency government’s decision a couple of months earlier to impose an exorbitant 30 percent increase in land revenue assessment.
• This decision was taken based on the recommendation of a Provincial Civil Service officer who argued that farmers were enjoying greater prosperity in the region following the establishment of the railway line in the Tapti River Valley.

Additional Information

• The Bardoli Taluk in modern-day Gujarat was hit by floods and famines in 1925, which adversely affected crop yield. This affected the farmers financially.
• Despite petitions and appeals from civic groups and farmers to review this unjust hike in tax rates in lieu of the grave situation, the government decided to go ahead with tax collection.
• Farmers in Bardoli invited Vallabhai Patel to launch the protest movement wherein all of them resolved not to pay taxes.
• Under the leadership of Patel, the Bardoli peasants decided to refuse payments of the revised assessment until the Government appointed an independent tribunal or accepted the current amount as full payment.
• Those who opposed the movement had to face a social boycott.
• The outcome of the satyagraha was British Government set up the Maxwell-Broomfield commission, reduced land Revenue to 6.03%, and returned confiscated land back to farmers.
• In this struggle, Vallabhbhai Patel got the title of “Sardar” by local farmers of Bardoli.

The correct answer is Tropical Evergreen.

Key Points

• The tropical evergreen woodlands are home to rubber. Rubber is extracted from tropical tree latex.
• Certain commercially significant trees, such as ebony, mahogany, rosewood, rubber, and cinchona, can be found in tropical evergreen forests.The Hevea brasiliensis is the most significant.
• Rubber trees reach heights of 20 to 30 meters. Growing rubber requires a hot, humid climate with 200 cm of annual rainfall spread out throughout the course of the year. Low temperatures and dry spells are bad for the crop.
• Rubber plantations thrive in well-drained loamy soils at elevations between 300 and 450 meters above sea level. Higher altitudes are not suitable for growing rubber crops. India is the world's third-largest producer of natural rubber. It follows Indonesia and Thailand.
• Rubber is used to make tires, tubes, and many other items needed for industrial use in addition to being used to erase pencil lines.
• Kerala saw the establishment of India's first rubber plantations in 1895, situated on steep hillsides. In 1902, the first rubber product was sold for a profit.

Additional Information

• Tidal - River deltas are home to tidal woods.
• Himalayan - The mountainous regions are home to Himalayan vegetation.
• Tundra - The arctic regions and high altitudes are home to tundra forests.

CONCEPT:

Acceleration Due to Gravity:

• The force of attraction exerted by the earth on a body is called gravitational pull or gravity.
• We know that when a force acts on a body, it produces acceleration. Therefore, a body under the effect of gravitational pull must accelerate.
• The acceleration produced in the motion of a body under the effect of gravity is called acceleration due to gravity, it is denoted by g.

• The acceleration due to gravity on the surface of the earth is given by,

CALCULATION:

• The gravitational acceleration of the earth at a height equal to half of the radius of the earth is given as (h = R/2),

• The gravitational acceleration of the earth at a depth equal to half of the radius of the earth is given as (d = R/2),

By equation 1 and equation 2,

• Hence, option 2 is correct.

Additional Information

• The acceleration due to gravity below the surface of the earth is given as,
• Let M be the mass of the earth, R be the radius of the earth g_d be gravitational acceleration at depth d from the earth surface
• g be gravitational acceleration on the earth's surfaces.
• ρ  be the density of the earth.
• P be the point inside the earth at depth d from earth surfaces.

∴ CS - CP = d, ∴ CP = R - d      ..............(1) (since CS = R)

gd = acceleration due to gravity at depth 'd'

The correct answer is A - 2, B - 3, C - 4, D - 1.

Important Points

• The Indian Association was the first avowed nationalist organization founded in British India by Surendranath Banerjee and Ananda Mohan Bose in 1876.
• The Poona Sarvajanik Sabha was founded in 1876 at Poona. It was founded by Mahadev Govind Ranade, Ganesh Vasudeo Joshi, S. H. Chiplunkar.
• Bombay Presidency Association founded in 1885 by Phirozshah Mehta, K.T Telang and Badruddin Tyabji.
• Madras Mahajana Sabha was established by S. Ramaswami Mudaliar and P. Anandacharlu in 1884.

The correct answer is Option 2.

Key Points

• There are a total of 16 railway zones in India, divided into 6 regions.
• The West Central Railway zone covers the states of Chhattisgarh, Madhya Pradesh, and Maharashtra.
• The South East Central Railway zone includes the states of Chhattisgarh, Odisha, and Jharkhand.
• The East Central Railway zone includes the states of Bihar, Jharkhand, and Uttar Pradesh.
• The North Eastern Railway zone includes the states of Assam, Bihar, Jharkhand, and Uttar Pradesh.
• Thus, from the given options, Jabalpur, Bilaspur, Gorakhpur, and Hajipur are the headquarters of West Central, South East Central, North Eastern Central, and East Central Railway zones respectively.

The Correct answer is Plastids are present in plant and animal cells.

Concept:

• Cell organelles are specialized structures within eukaryotic cells that perform specific functions.
• The presence of organelles differs in plant and animal cells.

Plant Cell -

• A plant cell is bound by a cell wall that is made up of cellulose.
• It contains organelles like the nucleus, mitochondria, vacuoles, Golgi bodies, and endoplasmic reticulum.
• It also contains an additional organelle called a plastid.
• The plastids are of 3 main types:
  • Chloroplast - contains chlorophyll and carries out photosynthesis.
  • Chromoplast - contains other pigments like xanthophyll, etc. that give color to fruits and flowers.
  • Leucoplast - does not contain any pigments and helps in the storage of materials.

Animal Cell -

• An animal cell lacks a cell wall and is only bound by the cell membrane.
• It contains important organelles like the nucleus, mitochondria, vacuoles, Golgi bodies, and endoplasmic reticulum.
• Plastids are not found in animal cells.
• However, they usually contain lysosomes and centrioles, unlike plant cells.

Explanation:

• prokaryotic and eukaryotic, have a cell membrane (also known as the plasma membrane). The cell membrane provides a protective barrier for the cell, controls the passage of substances in and out of the cell, and maintains the cell's osmotic balance.
• "Plastids are present in plant and animal cells." This statement is actually also incorrect; plastids are not found in animal cells. Plastids, which include chloroplasts, are organelles found primarily in plant cells. They are involved in the synthesis and storage of food and contain pigments that capture or reflect light. Animal cells do not possess plastids.
• "Cell membrane is present in both animal and plant cells." This statement is correct. Both animal and plant cells have a cell membrane that controls the movement of substances in and out of the cell. In plant cells, this cell membrane is inside the cell wall.
• "Cell wall is present in plant cell only." This statement is mostly correct. The cell wall is indeed a characterizing feature of plant cells, where it provides structure and support. However, it is worth noting that cell walls are not exclusive to plant cells. They are also present in other organisms such as fungi and bacteria.

The correct answer is A.

Key Points

Vitamin A:

• Vitamin A is an important vitamin that plays a major role in our vision.
• It helps in the production of certain pigments that are important for the proper functioning of the retina. 
• Vitamin A deficiency is the major cause of severe diseases, infections and preventable blindness in children.
• It is one of the major causes of night blindness in pregnant women.
• It also affects the immune system and results in deaths from malaria, diarrhoea and measles.
• Night blindness is a disease that is caused due to deficiency of vitamin A in food.
  • ​Night blindness (nyctalopia) is a condition in which people are unable to see clearly at night or in dim light.
  • The formation of retinal, a component of rhodopsin, requires vitamin A.
• Some of the food sources of vitamin A are vegetables, fruits and dairy products.

CONCEPT:

Human Eye:

• The human eye is one of the most valuable and sensitive sense organs.
• It uses light and enables us to see the colourful world around us.
• The human eye is more or less like a photographic camera.
• The lens system of the eye forms an image of an object on a light-sensitive screen.​

Functions of Parts:

• Cornea: The cornea is the outer transparent part of the eye that protects the eyes from external agents. 
• Iris: Iris controls the pupil which controls the amount of light. Iris gives distinct colour to the eyes. The brown eye or blue eye actually is the colour of the iris. 
• The eye lens is a spherical lens that forms an image of the object on the retina. 
• The retina is a screen that sends information to the brain through the optic nerves. 
• The focal length of the eye lens is maintained by the ciliary muscles. It reduces the focal length by stretching itself to see nearby objects and relaxes to increase the focal length to see far objects. 
• This is an anatomical detailed diagram of a human eye
•  The eye lens is a transparent, biconvex structure in the eye that provides finer adjustment required to focus objects on the retina.
• And iris is a Dark muscular diaphragm between the cornea and the lens that controls the size of the pupil.
• The retina is the light-sensitive surface of an eye on which the image is formed it generates signals which are transmitted to the brain through optical nerves
• Hence, the eye lens is just like an ordinary bifocal convex lens which will act as a converging lens.

EXPLANATION:

• The lens system of the eye forms an image of an object on a light-sensitive screen.
• The Eye lens is a transparent, biconvex structure in the eye which provides finer adjustment required to focus objects on the retina.

​The correct option is 1^st.