If there are n1 discs on the driving shaft and n2 discs on the driven shaft in a multi-plate clutch, then the number of pairs of contact surface is

If there are n1 discs on the driving shaft and n2 discs on the driven

1.	If there are n1 discs on the driving shaft and n2 discs on the driven shaft in a multi-plate clutch, then the number of pairs of contact surface is
A.	n1 + n2
B.	n1 + n2 - 1
C.	n1 + n2 + 1
D.	n1 + n2 + 2
Answer» C. n1 + n2 + 1