问一道数学题

If a committee of 3 people is to be
selected from among 5 married couples so that the committee does not include
two people who are married to each other, how many such committees are
possible?

A.    20

B.     40

C.     50

D.    80

E.     120

10*9*8 / 3*2 = 120, each married couple could be teamed up with 8 different people. 那么5个couple就有40个不同的组合。 120 - 40 - 80