From how many different sets of three paintings does Greg have to choose?

Greg has nine paintings. The Hickory Museum has enough space to display three of them.

From how many different sets of three paintings does Greg have to choose?
A . 27
B . 56
C . 84
D . 168
E . 504

Answer: C

Explanation:

Be careful not to count the same set of three paintings more than once C order is not important. A ninechoose-three combination is equal to