【单选题】Frank Webb, an American pilot who first flew a glider at the age of 14, made his first flight alone on his 16th birthday and got his commercial pilot's license(执照) on his 18th birthday. After serving ...
A.
he was afraid of the influence of 'Sept. 11'
B.
he got a better pay there than in the US
C.
he thought more for his children
D.
he hoped to see the beautiful sights in China