I think the answer is all
The first answer is correct: "They suggest that the heat is stifling, giving the poem an oppressive mood".
The author begins the poem with the sentence cited above. The use of the expression "rend open" plus the use of the imperative mode, suggest some sort of desperation caused by the heat. That is why the author prays for wind (an unbeatable natural force) to come and defeat heat, ending the suffering.
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
