The correct answer is D. The grain contains all three parts of the kernel.
A wholegrain refers to a grain that contains all three original parts of the kernel: the bran, the endosperm and the germ (refer to attached image). A wholegrain, unlike a refined grain is not processed and has all three parts of the kernel intact. Examples of wholegrain food sources include barley, brown rice, oatmeal, whole wheat pasta, etc.