问题详情

News Item Two (21-22)
The Space Shuttle Discovery made a real night landing at the Kennedy Space Center early on Thursday. The night landing, the 11th in the centre’s 94 shuttle missions, ended a 10-day mission to outfit the orbiting international space station. Although the space craft created a solid boom that can be heard along much of Florida’s eastern seaboard, witnesses on the ground could not see the orbiter until it was directly over the one-way lights. Scattered showers off the Florida coast had threatened to postpone the shuttle’s return. But broadcasters gave a green light when they decided no rain will fall within 48 kilometres of the space centre.
21. The space shuttle Discovery completed a ___mission upon to the Kennedy Space Centre.
A. 11-day
B. 94-day
C. 10-day
D. 49-day请帮忙给出正确答案和分析，谢谢！