As a tool for public health policy, the epidemiological study of disease has one major advantage over experiments studying the effects of toxic substances on animals: there is never any call for extrapolating inferences across species in epidemiology.
Which of the following can be inferred from the passage above?
A.In epidemiology, extrapolating inferences across species is only an auxiliary tool.
B.Epidemiology is a very precise science.
C.In epidemiology, human populations are studied directly.
D.Toxicological experimentation on animals is more expensive than are epidemiological studies.
E.Toxicological experimentation on animals yields results less quickly than do epidemiological studies.