Task: Question Answering
Input (English): Problem: in a room filled with 7 people, 2 people have exactly 1 sibling in the room and 5 people have exactly 2 siblings in the room. if two individuals are selected from the room at random, what is the probability that those two individuals are not siblings ?
Options: a. 5 / 21, b. 3 / 7, c. 4 / 7, d. 5 / 7, e. 16 / 21
Output (English): b