Question

Which causes only chemical weathering?

Answer 1

A.
oxygen

B.
wind

C.
ice

D.
plants

Answer 2

hint:
that chemical weathering type is an oxidation reaction

Answer 3

The key here is only Chemical. an example of chemical weathering is water passing over a piece of Iron constantly. The Iron may be able to withstand the force for many years but the Oxygen in water would cause rusting as it bonds with the Iron to form IronOxide.
B is wrong because- Wind smooths objects out and eventually blows them away into dust.
C is wrong because- Ice causes an expanding pushing force that is physical.
D is wrong because- A plant will also cause a pushing force cracking things into pieces.
I hope this helps you understand weathering a little better.