The roots turn downward. The roots move horizontally. The leaves face toward the Sun. The stems curl around supports.
I gave my students this multiple choice question: How do sprouting plants exhibit positive gravitropism?

Only one answer is correct among these 4 choices:
- The roots turn downward.
- The roots move horizontally.
- The leaves face toward the Sun.
- The stems curl around supports.

Could you tell me which one is correct?

The roots turn downward.