Pneumonia is closely related to ______.

A．the changes inside human bodies are more important than exterior ones
B．the loss of competence is more significant than that of cells
C．the shrinkage of muscles is more significant than the decline in height
D．the thinning of hair is less important than the wrinkling of skin

A．If a parent suffers from it, it is most likely that the child also does.
B．If a person has high blood pressure, he is more likely to contract it.
C．If a person smokes, he is most likely to contract it.
D．If the environmental factors are properly controlled, it can be prevented.