For capital letters, we can just add the ending -s, for example:
I got As in the final exam.
for lower-case letters, an apostrophe is used to avoid confusion:
In the multiple-choice exam all the correct answers happened to be a's! (as in: option a)
D To persuade the audience to use non violent means for protesting.
What book is this question asking about?
Today I cleaned my room, played softball and went to a concert.
This is the correction I can provide for you.
