—What is population of China? —China has population of l3 billion．A．the；the B．a；a C．a；th

问题补充：

—What is population of China?

—China has population of l．3 billion．

A．the；the B．a；a C．a；the D the；a

答案：

解析：population“人口”，如有地点名词修饰，需加“the”；如有数字修饰，则需加“a”