The Great Depression in 1929 was caused by all the following BUT

The Great Depression in 1929 was caused by all the following BUT______.
A、stock market speculation
B、over-expansion of credit
C、too much investment in companies
D、lack of stability in the banking system
【正确答案】：C
【题目解析】：本题考查美国的经济大萧条。根据课本P２１０可知，1929年的大萧条是由股市投机、信贷过度扩张、银行体系缺乏稳定造成的。