D. 226.08cm^2
Since we are finding the combined area of the two bases of the cylinder, we are adding the area of the first base with the second base. The formula for the base of a cylinder is pi x r^2, since it is a circle. Since the bases are the same, we can rewrite this as 2pi x r^2.
Since the diameter is 12cm and r = 1/2 diameter, r = 6cm.
Thus, A = 2(3.1415)(6)^2 = 226.08cm^2
