Which influences both mechanical and chemical weathering
a. plants
b. wind
c. iron
d. tectonic plates

The correct option is A.
Plants can participate in both mechanical and chemical weathering of rocks. Mechanical weathering occurs when rocks are broken into smaller particles as the result of the roots of plants which grows and push them apart. Chemical weathering occur when the plant roots release chemicals, such as acids, which help in breaking down the rock particles.

Answer glacier terminus;