In a room there are 7 people. Each person shook hands with every other person. How many hand shakes were there?  Pick:
A) 19
B) 20
C) 21
D) 22
E) 23
7212 = 21   The answer is 21.
<result>C</result>
In a room there are 7 people. Each person shook hands with every other person. How many hand shakes were there?