Answer:
None, both objects will hit ground at the same time.
Explanation:
- Assuming no air resistance present, and that both objects start from rest, we can apply the following kinematic equation for the vertical displacement:

- As the left side in (1) is the same for both objects, the right side will be the same also.
- Since g is constant close to the surface of the Earth, it's also the same for both objects.
- So, the time t must be the same for both objects also.
The correct answer is A continúe moving with constant velocity
C weather or not the plants are exposed to sunlight