Science teachers need to ask more divergent questions because a. it stimulates and develops critical thinking. b. it directs students to correct answers. c. it helps develop thinking strategies d. it helps in assessing creative behaviour in a learner.

Divergent questions are open-ended and allow multiple possible responses, which stimulate critical thinking, develop thinking strategies, and help assess creativity. Statement b describes convergent questions, which lead to a single correct answer, not divergent questions. Hence a, c, and d are correct.