Hey Baldini, please try to use the spoiler to mask the OA. This will allow others to first take a go at the question & see if they are getting the same answer as the OA
The question is asking if n=2?
Stmt 1: Does not help. All prime numbers have exactly 2 positive integers. One itself & the other 1. Since cannot narrow down to one answer, this statement is not sufficient.
Stmt 2: Hmm...at first glance it is tempting to rule this option out (especially if you are running against time). Take any number greater than 1, the factors are:
2 = 1X2 (difference 2-1=1 is odd)
3 = 1X3 (difference 3-1=2 is even)
4 = 1X2X4 (difference 2-1=1 (odd), but 4-2=2 (even)) This is not good enough because the difference of any 2 factors should be odd. The same thing will happen with all other numbers.
The only number that has the difference of any of its factors as an odd number is 2. So, statement B is sufficient to answer the question.