Hyphens are so confusing, so I'm asking for a little help.

2.
Select the sentence which is correctly punctuated.
A) He came in for his follow up.
B) He came in for his followup.

My answer: B

4.
Select the sentence which is correctly punctuated.
A) He will follow-up in 4 weeks.
B) He will follow up in 4 weeks.

My answer: A

2 answers

Both of your answers are wrong. In sentence 2, follow-up is used as a noun. The right answer is not shown. In sentence 4, follow up is used as a verb.

"follow up (verb)
follow-up (noun)
follow-up (adjective)"

http://www.merriam-webster.com/dictionary/%20followup
12th gustion papar 21 feb 2012