X-Rays, or ______, are diagnostic tools used to visualize internal organs.

A. radiograms
B. sonograms
C.Radiographs
D. tomograms

is it C

X rays are just one type of radiograph. For visualization of internal organs, most would use other types of radiographs, such as gamma rays, or by other methods (PET, NMR, fluoroscope, or even ultrasound).

C is the best answer,however the question is lame, at the best.