In school, children are members of a small society that exerts a tremendous influence on their moral development. Teachers serve as role model to students in school; they play a major role in inculcating their ethical behavior. Inculcating values should not be an aim of science education at upper primary level.

BS Bloom has given Taxonomy of teaching objectives. Bloom's taxonomy refers to a classification of the different learning objectives that educators set for students. It divides educational objectives into three "domains": cognitive, affective, and psychomotor (sometimes loosely described as "knowing/head", "feeling/heart" and "doing/hands" respectively).

Science Fairs is co-curricular activity in Science teaching. A science fair is generally a competition where contestants present their science project, results in the form of a report, display board, and/or models that they have created. Science fairs allow students in elementary, middle and high schools to compete in science and/or technology activities.

The main limitations of the Project method of teaching Science is the students have to perform excessive mental and physical work. 
Hence, option A is correct.

Various commissions and committees on education set up by Government of India after Independence emphasized the teaching of science from the primary level. All of them emphasized the teaching of science for fundamental principles and concepts useful in daily life. The development of process skills like observation, classification, measurement, communication etc. To nurture the natural curiosity, aesthetic sense and creativity in pupils and enabling them to carry out innovations in science. Certain socially desirable habits like honesty, truth, tolerance, self-confidence, self-reliance etc. should be inculcated through the science. In search of the answers to ‘What’s’ and ‘Why’s’ and ‘How’s’ of the things teacher should encourage pupils to observe and accept the natural things as such.

When a candle lighted and it covers it with a jar. The candle stops burning after some time, because, the candle's flame is fueled by oxygen. When the jar is placed over the top of the candle, there is still oxygen for the fire to consume, but it is in a limited quantity. Once all of the oxygen contained within the jar is utilized by the flame, it no longer has its fuel and goes out.

In 'Heuristic method' children are encouraged to find out things for themselves. In 'Inquiry method' too, children are encouraged to create their own questions and arrive at the answer.

Observation schedule is a method in which data in the field is collected with the help of observation by observer. An observation schedule is an analytical form, or coding sheet, filled out by researchers during structured observation. It carefully specifies beforehand the categories of behaviors or events under scrutiny and under what circumstances they should be assigned to those categories.

Directing activities of teaching is the teacher of the student in conducting experiments, doing an observation on students in experimentation and analysis of laboratory findings and outcome-evaluation practice. So, helping in scoring high grades or marks is not the purpose of conducting practicals / experimental activities in science.

Diagnostic in nature is the key feature of Formative Assessment in Science.Formative assessment including diagnostic testing is a range of formal and informal assessment procedures conducted by teachers during the learning process in order to modify teaching and learning activities to improve student attainment. 
Hence, option B is correct.