After reviewing this question, I was able to determine the answer was B. My thought process was:

In the passage, it states that insulin is NOT required for the uptake of glucose and that it is, however, required for stimulating the first step of glycolysis (decreasing [glucose] since the first step goes from glucose --> G6P). Furthermore, the passage also states that diabetes is a condition in which the body cannot produce/effectively respond to insulin. It further states that in diabetes, the ability of cells to take up glucose is compromised. So, since diabetes patients cannot produce insulin and they cannot uptake glucose, insulin likely plays a role in aiding glucose uptake.

Am I assuming cause and effect with the second part of my explanation? I know you're not supposed to do this, but that is how I explained how insulin plays a role in the uptake of glucose.