Which activity would be within the field of biology?
a. designing a structure that would not fall in an earthquake
b. measuring the amount of energy wasted in an automobile
c. figuring out how pesticides affect plant growth

(c). Figuring out how pesticides affect plant growth

Explanation:

Biology can be defined as a branch of science, which includes study of living organisms, their chemical processes, physical structures, development, molecular interactions, and physiological mechanisms.

As in last option, effects of pesticides is tested in plants, which are living organisms, this activity would be within the field of biology.

Thus, the correct answer is option (C).