GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - Q7Y4U7NJV1P67B84J

According to the passage, which of the following is true of the water management systems in the central and southern Maya Lowlands? A. They were implemented in part because of the prevailing pattern of rainfall. B. They were an integral part of lowland cities' architecture. C. They were needed because of insufficient resources such as ponds, rivers and lakes in the lowlands.