Which of the Following Organic Molecules Contains at Least One

Which of the following organic molecules contains at least one functional group?

A) All of these molecules contain at least one functional group.
B) All of these molecules except I contain at least one functional group.
C) Molecules II, III, and IV contain at least one functional group.
D) Only molecules III and IV contain a functional group.
E) None of these molecules contain a functional group.