A meeting has to be conducted with 4 managers. Find the number of ways in which the managers be selected from among 7 managers, if 2 managers will not attend the meeting together?  Choose the most appropriate option.
A) 25	B) 20	C) 35	D) 36	E) 38

Rationale: "we can either choose all 4 people from 5 manager who have no problems or choose 3 from the 5 and 1 from the 2 managers who have a problem sitting together so 5 c 4 + ( 5 c 3 * 2 c 1 ) this is 5 + 20 = 25 answer : a"
Answer: A