The weakening of rock due to expansion and contraction resulting from temperature changes is known as A. thermal stress. B. leaching. C. exfoliation. D. haloclasty.

Answer: Option (A)

Explanation:

Thermal stress is also known as insolation and it is a physical weathering process in which the rocks becomes weak and and shatters due to the fluctuating temperature condition. It is a common type of weathering process. For example, a rock getting heated up in the day time and at night it cools again, thereby breaking the rocks apart.

Thus, the correct answer is option (A).