PS Archive | The president of a company wants to fire 3 persons from the Sales depa

The president of a company wants to fire 3 persons from the Sales department. How many distinct selections can he make if the Sales department gathers 8 sales managers?
(A) 366
(B) 3
(C) 8
(D)112
(E) 56

Hi. Could you help me to solve this problem? I got an answer 336 = 8*7*6, but my book doesn't provide such solution. Actually, on the answer page it says that correct answer is (E)! I've already had problems with wrong answers in my book, therefore I need your help to figure out this case.
Thank
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