Answer:
This essay is about when I misjudged someone. So what happened exactly? I was in school one day and there was a new girl. I thought she was pretty nice so I went up to her and talked to her. She turned out to backstab me and tell all of my secrets to every months into our friendship. I misjudged someone by thinking they were nice when in reality they were a really mean person.
The answer is "All of the above"
B. While Bertie was away, Miss Paxton ran the office, made executive decisions, and gave herself a long raise.
Colons should only be for an ordered list, so the colon should come after Miss Paxton, not before. Semi-colons are used to separate two phrases that could be a sentence, so A is not correct either. B is therefore the correct answer because the comma has multiple purposes.