Task: Question Answering
Input (English): Problem: in a room filled with 7 people , 3 people have exactly 1 sibling in the room and 4 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 ) 13 / 21
Output (English): e