问题补充：
----is the population of your city?
-----About two million.
A. How many
B. How much
C. What
D. Which
答案：
A. How many
B. How much
(答案→)C. What
D. Which
解析：How many多少个；How much多少元；What什么；Which哪一个；根据下文，大约两百万。可知上文问的是，你们城市的人口是多少？英语中提问population时，一般用疑问词what，故选C。
