Fats are used for energy after they are broken into fatty acids. Protein can also be used for energy, but the first job is to help with making hormones, muscle, and other proteins. Broken down into glucose, used to supply energy to cells. Extra is stored in the liver.
I believe the answer is B
The answer is "PET scan" or "PET-CT".
PET scan or positron emission tomography uses the technology behind conventional CT scans but performs to quantify the function in specific parts of organs (i.e. brain). The patient will be given a positron emitting substance most commonly fluorodeoxyglucose or FDG via intravenous injection. After which, the patient will go to the PET machine and the PET machine will measure the positron emitted throughout the body. Positron is well correlated to the function of a specific part of an organ.