Answer: B
Step-by-step explanation:
The water was provided, and carefully controlled, by a combination of natural springs and artificial constructions such as aqueducts, dams, canals, reservoirs, and gates. One of the most impressive of these was the 16 km d built by Nezahualcoyotl on the edge of Tenochtitlan to block the salty water of Lake Texcoco and create a lagoon supplied by a fresh water spring.