The correct answer is D. As it glowed in the sky, the wolf howled at the moon.
Explanation:
In grammar, a misplaced modifier occurs when a word or set of words that describe or modify a noun such as an adjective, adverb or modifier phrase is placed incorrectly as it is separated from the word it modifies, which lead to a strange or confusing construction. Considering this, from the options provided the sentence with a misplaced modifier is "As it glowed in the sky, the wolf howled at the moon" because in this sentence the modifier that describes the moon is "As it glowed in the sky" but this has been incorrectly separated from "moon" and placed beside "the wolf" which creates a strange construction as it seems it is the wolf the one glowing in the sky, this mistake can be corrected by placing the modifier correctly as "As the moon glowed in the sky, the wolf howled at it".