Which question can be answered by following the scientific method?

a. What was the highest temperature that was recorded yesterday?

b. What is the most interesting aspect of the light-dependent reactions?

c. How does a change in temperature affect the stomata of a plant?

d. how many stomata are there on this leaf?

The correct answer is c. How does a change in temperature affect the stomata of a plant?. This can be discovered using the scientific method. The number of stomata changes from plant to plant and leaf to leaf, and what the highest temperature was is impossible to know because we don't specify where. Being interesting is subjective so it can't be studied.