Because we have two fractions that do not have the same denominator, we must convert these fractions to a common denominator:
2/7, 5/9
7 * 9 = 63
2 * 9 = 18
Our first fraction is 18/63
9 * 7 = 63
5 * 7 = 35
Our second fraction is 35/63
Now we have 5 18/63 and 3 35/63
Now we can add these fractions much easier.
18 + 35 = 53/63
5 + 3 = 8
We're left with 8 53/63
We can round this up to 9.
Your answer is B.