I wud say A...
(1) is obvious..
(2) lets say r=6 and s=12
then the prime factors of 6 are 2,3 and the prime factors of 12 are 2,3
6/12 is not a integer
however if r=12, s=6....then obviously r/s is an integer...
Note: the question stem is not very clear, it should say distinct prime factors...which is what I would take to be the case here...
So if we assume that the stem is: prime factors instead of distinct prime factors it means that factoring 12= 2x2x3=
We would include 2 twice..right? and therefore r/s would be an integer?
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