The correct option is B m=2, when n is prime.
We know, for n to be a prime number, have only two factors 1 and n.
So, possible orders are 1×n or n×1. and
for non-prime number (n≠1), have more than two factors.
So, for non-prime numbers (n≠1), will have more than two possible orders.
But 1 is not a prime number and for that only one possible order, i.e. 1×1.