According to N.C.F. 2005 in the upper primary stage science curriculum, Which of the following is recommended?

a. Concepts should be linked to everyday life experiences using concrete examples.

b. Learners should be engaged in simple activities, group work, models and projects, etc.

c. Learners can be introduced to abstract concepts of science by involving in systematic experimentation.

d. Emphasis is given to the depth of science by involving them in advanced technological experiences.