there are four people in a room.for every two people are connected if:-they are friends,or

问题描述:

there are four people in a room.for every two people are connected if:-they are friends,or
-a third person is friends both of them,or -they have different friends who are friends of each other.
what is probability that every pair of people in this room is connected?
A)18/32 B)20/32 C)22/32 D)19/32

just take a guess...