一道简单的英语题

题目

一道简单的英语题
Most have been lost on fiying up or landing because those are the most difficult times of any flights.
The most difficult times of a flight are_________________
A.taking off
B.flying up and arriving
C.entering the orbit and landing
D.leaving the earth and entering the orbit
根据上面一段话选答案
= =。。。。三个不同的答案。。。。

答案

问题补充：根据上面一段话选答案= =.三个不同的答案.Most have been lost on （fiying up or landing）because those are the most difficult times of any flights.those 指括号里面的.A起飞B.flying up and arrivi...