If 11 persons meet at a reunion and each person shakes hands exactly once with each of the others, what is the total number of handshakes?  Choose the most appropriate option:
A) 11 × 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1  B) 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1  C) 11 × 10  D) 55  E) 45
Total number of handshakes = C112=11∗10/2=55   Answer: 55
<result>D</result>
If 11 persons meet at a reunion and each person shakes hands exactly once with each of the others, what is the total number of handshakes?