The fourth revision is correct. it says who was strolling in the sidewalk.
The sentence that correctly uses the word "principal" is the second sentence. The word "principal" refers to the person who has the highest authority in an institution, particularly as referred here, which is a school. On the rest of the sentences, the right word to be used is "principle" and not principal.
Answer:
chopin “A Pair of Silk Stockings”
Explanation:
<span>she has become a hardened and angry woman</span>