Mechanical weathering is more rapid in a climate.
a. dry
c. cold
b. hot
d. humid

the answer is cold   hope this helps :)

(C) Cold

Explanation:

The mechanical weathering is the type of process in which the big rocks are break into the small number of pieces and this process is basically happened on the surface of the planet.

In the cold climate, the mechanical weathering occur more rapidly as compared to the other climate such as dry, hot and humid climate.

The main reason behind this process is due to the frost scattering as the water get start flowing into the cracks of the rocks. The following are the main factors which affect the mechanical process weathering are:

polar areas, such as antarctica or the south pole.