Answer: A

Statement 1 alone is sufficient but statement 2 alone is not sufficient to answer the question asked.

I'm very confused... what does m have to do with anything?

The question you posted is the equivalent of:

What's the value of x?

(1) x = 10

(2) y = 5

This Question is exact copy and paste from Gmat Prep software.

OA is B, but I think it should be D.

Here is the reasoning
m, n are intergers and n> 0, m >0

1) gives value of n so suff

2) gives value of m, so it will look like that it is irrelevant to answer the question.

But if you look closely at the equation it is equal to 9^2n+1
So if you substitute various values for n such as 1, 2, 3 etc . you will notice that remainter is always 9. Hence Suff!

Because 1 and 2 are suff therefore answer should be D.

I agree that any power of N divided by 10 will give remainder as 9.