The modern people like travelling now because（）

A．he founded America
B．he invaded America
C．he was a brave man
D．he discovered the continent of America

A．they found it no use doing so
B．they liked staying at home
C．there was no modern transportation
D．they were forbidden to go to other countries

A．it is interesting
B．it is cheaper than to go in any other way
C．it can cross the wide oceans
D．it takes less time