Answer:
The answer is indeed letter B. When she mimicked a chicken was the funniest part of the speech.
Step-by-step explanation:
The main reason why the structure in option B sounds strange is the fact that, in the English language, the subject usually comes first in a sentence. However, in this option, its position has been inverted. The whole sentence "when she mimicked a chicken" functions as a predicate to the subject and should come after the linking verb "was".
Thus, it would sound more appropriate if we placed the subject and the predicate in their original places:
- The funniest part of the speech was when she mimicked a chicken.