问题补充：
it is to jump out of an airplane at 10,000 feet!
A. What an exciting experience
B. How exciting experience
C. How an exciting experience
D. What exciting experience
答案：
A. What an exciting experience
B. How exciting experience
(答案→)C. How an exciting experience
D. What exciting experience
解析：考查感叹句。感叹句结构为：What+(a/an)+（形容词）+单数可数名词+主语+谓语！或How+ adj.（adv.）+主语+谓语+(it is)。故选C。
