问题详情

Which of the following is true？
A．To understand Vienna, one must know its trade.
B．After World War Ⅰ, about 7,000,000 people lived in Vienna.
C．Green woods, mountains and a large river surround Vienna and make it a beautiful city.
D．Vienna musicians did little to make Vienna a city of spirits.请帮忙给出正确答案和分析，谢谢！