Answer:
B. consider whether he ought to go back to find more evidence
C. think about whether he needs to change his perspective
Explanation:
When making research and the researcher discovers that his initial ideas support a different perspective, he should consider whether he needs to go back and get more evidence and whether he needs to change his perspective, so that the ideas would match the perspective.
In these lines, the poet metaphorically compares the fog to cat. Answer is B. a cat. Hope it helped you, and have a great day.
-Charlie
