The major disadvantage of air transportation compared with land transportation is that

A.

an aircraft can fly above terrestial obstacles and therefore has a much wider choice of routes

B.

air transport is much more expensive to develope, build and maintain

C.

air transportation is faster in speed, enabling to make much more frequent runs

D.

air transportation is much more suitable for international information exchange systems

E.

air transportation is much more flexible

Correct answer is B

No explanation has been provided for this answer.