【单选题】

{{I}}Questions 17-20 are based on a monologue about the growth ofDetroit, a large industrial city inAmeric

A、You now have 20 seconds to read Questions 17-20.{{/I}} What is the main topic of the talk
A、The growth ofDetroit as an industrial city.
B．Detroit, the fifth largest city in the U. S.
A、
C．The geographical advantages ofDetroit.
D．The car industry in the U. S.
A、