Answer is C. 
First start by subtracting the exponents from top to bottom
let's start with a so a^2 - a^-2 2 - (-2) = 4
Now B: b^-3 - b^2 so -3 - 2 = -5
This leaves you with a^4 b^-5
However you cannot have a negative exponent so B must cross over and move to the bottom to become positive
Don't forget about the squared outside the parentheses. Both exponents must be multiplied by two to get 8 and 10
First start by subtracting the exponents from top to bottom
let's start with a so a^2 - a^-2 2 - (-2) = 4
Now B: b^-3 - b^2 so -3 - 2 = -5
This leaves you with a^4 b^-5
However you cannot have a negative exponent so B must cross over and move to the bottom to become positive
Don't forget about the squared outside the parentheses. Both exponents must be multiplied by two to get 8 and 10