The ancient Nubians inhabited an area in which typhus occurred, yet surprisingly few of their
skeletons show the usual evidence of this disease. The skeletons do show deposits of
tetracycline, an antibiotic produced by a bacterium common in Nubian soil. This bacterium
can flourish on the dried grain used for making two staples of the Nubian diet, beer and
bread. Thus, tetracycline in their food probably explains the low incidence of typhus among
ancient Nubians. Which of the following is an assumption on which the argument relies?
A. The tetracycline deposits did not form after the bodies were buried.
B. The diseases other than typhus to which the ancient Nubians were exposed would not be
affected by tetracycline.
C. Typhus is generally fatal.
D. Nubian grain became contaminated with tetracycline-producing bacteria prior to being
harvested.
E. Bread and beer were the only foods eaten by the ancient Nubians which could have contained
tetracycline.
OA A