試題詳解

48. Based on contextual clues, what does an epidemiologist study?
(A)   how diseases are found. spread. and controlled in groups of people
(B)   how synthetic materials can be developed for medical applications
(C)   how characteristics are passed down to children by parents' genes
(D)   how diets and supplementary nutrients influence human health
(E)   the characteristics and effects of poisons and toxins