Nervous system is what your ooking for
The correct answer is letter C. G<span>erontogastroenteroepidemiology would probably deal with the study of stomach and intestinal epidemics that strike the aged.
"Geronto" - age
"Gastroentero" - stomach and intestines
"Epidemio" - epidemic
"logy" - study of</span>
It helps the person get closer and communicate with that person at face value. Working together strengthens the bond.
I would say the answer is either A or B. Hope this helps!