Whenever you are asked to find the number of square feet covered by something, you are finding an area. To find the area of Jason’s circle, you first need to figure out if you have been given the radius or the diameter. By definition, the diameter of a circle is the longest distance across the circle, so we know here that the diameter is 8 feet. This means that the radius is 4 feet. So...
A = π(4)2
= 16π
≈ 50.2 square feet
So, Jason’s circle will cover about 50.2 square feet of his wall (and B is the closest one to that)