A) to describe what gargoyles look like and their purpose is the correct answer.
Explanation:
This excerpt has two paragraphs and each of them has a specific function. In the first one, the speaker compares gargoyles with animals or mythological creatures in order to explain how they look like. In this paragraph, the purpose of building gargoyles is also mentioned (transport water away from roofs and sides of buildings.)
In the second paragraph, the speaker points out how gargoyles looked in ancient times, and then he explains the evolution of their appearance across history. This is why option A is the correct answer.
