The formula for a cylinder is πr²*h where r is the radius and h is the height:
1.) Plug in r for 4, as the radius is 4
π(4)²*h
2.) Plug in h for 8, as the height is 8
π(4)²*8
3.) Simplify 4²
π(16)8
4.) Simplify 16*8
π128
5.) Don't forget your units, inches cubed (because you multiplied three dimensions all with inches, which results in the inches being multiplied three times as well)
π128 in³ or 128πin³
It is the third answer choice, hope this helped :)