[The city’s engineers excelled in areas] neglected by the Greeks, such as the construction of roads and aqueducts, and of sewers that could wash the filth of the city into the Tiber. They have built paved roads throughout the country, leveling ridges and filling up hollows, so as to make possible the movements of heavily loaded wagons. . . . And such is the quantity of water brought in by the aqueducts, that veritable rivers flow through the city and its sewers: almost every house has cisterns, waterpipes, and copious fountains.” —Strabo, as quoted in
Empires Ascendant: Time Frame 400 B. C.–A. D. 200

Where did the sewage of Rome finally end up?
a.
in the aqueducts
b.
in the sewers
c.
in the Tiber
d.
in heavily loaded wagons