Hi all!

Does anyone know what the rules are for capitalization and punctuation when writing a multiple choice quiz? I've tried checking various quiz websites, but there doesn't seem to be a consensus. Even professional sites aren't consistent from quiz to quiz. Sometimes they capitalize single-word answers and sometimes they don't. Sometimes they capitalize the first word of incomplete sentences and sometimes they don't. Sometimes they punctuate every sentence, and sometimes they only put a period at the end of the last sentence. Other times they don't punctuate them at all.

Could someone please tell me if the following are gramatically correct?

Example 1

How many apples were there?

A) one
B) four
C) nine

Example 2

What does the boy want to be when he grows up?

A) a policeman
B) a doctor
C) a scientist

Example 3

Why did the girl open the window?

A) so she could look at the stars
B) it was hot
C) to wave to someone

If incomplete sentences (as in A and C) don't start with a capital letter and aren't punctuated, what happens when one of the answers is a complete sentence (as in B)? Should it be written as complete sentences are normally written. Or does the format of the quiz override the usual considerations?
There are really no rules for such matters and, as you say, there seems to be no consensus.

Best wishes, Clive