Which of the following attributes of oxygenated blood makes functional MRI (fMRI) possible? A. It can be seen using x-rays. B. Active areas of the brain take up more oxygenated blood than they need for their energy requirements. C. Active areas of the brain take up less oxygenated blood than they need for their energy requirements. D. It can be labeled with radioactive fluorodeoxyglucose (FDG).

Our brain requires an enormous measure of vitality and so as to meet this needs the progression of blood must be accurately arranged to guarantee that oxygen is being conveyed where it is required and when it is required.
Vitality in the mind is created solely from a type of digestion that requires oxygen. However, neurons just keep up a little save of vitality and these cells require a constant inventory of oxygen, particularly when the cells are terminating and speaking with their neighbors.
Blood dashing through a brain district's trap of vessels is an indication that nerve cells in that region have kicked vigorously. The blood races to dynamic territories to supply terminating neurons with the oxygen and glucose they require for vitality.
Hence, the correct answer is option B "Active areas of the brain take up more oxygenated blood than they need for their energy requirements"