Carbohydrate provides 4 calories per gram, protein provides 4 calories per gram, and fat provides 9 calories per gram.
After reading the following options, the correct one is the third option, PET scans will use tracers to inject in a vein in someone's arm. Then, the organs as well as tissues will absorb the tracer. This information makes the third option correct because PET scans mostly work with your tissues to see if there are any diseases someone may have in their body.
Hope I helped! :)
Peaculiar
