【单选题】

Modern life is impossible without traveling. The fastest way of traveling is by plane. With plane you can travel in one day to places which needed a month or more to get to hundreds of years ago.

Traveling by train is slower than by plane, but you can see the places you are traveling through. They make the longest journey enjoyable.
Some people prefer to travel by seA、Ships are not so fast as trains or planes, but traveling by sea is a very pleasant way to spend a holiday.
Many people like to travel by car. You can make your own timetable. You can travel three or four hundred miles or only fifty or one hundred miles a day, just as you like. You can stop if there is something interesting. That’s why traveling by car is popular for pleasure trips, while people usually take a train or a plane when they travel on business.
Which of the following is the fastest way of travelingA．By air.
By train.
C．By boat.