There were 5 pupils in a room. Each pupil shook hands once with each of the other pupils. How many handshakes took place?
A 5
B 10
C 15
D 20
F
There were 5 pupils in a room. Each pupil shook hands once with each of the other pupils. How many handshakes took place?
A 5
B 10
C 15
D 20