单项选择题

Many people prefer (21) by air. This is (22) it has some advantages. First, it is the (23) means of transportation today, and (24) takes the least time for people to travel from one place to another, thus (25) them a lot of time. (26) , it is very comfortable. The friendly hostesses will (27) you carefully. On long flights, there are films and music for you.
On the other (28) , traveling by air has its (29) . Perhaps the most obvious (明显的) one is it’s more dangerous. We often hear Of the news about hijackings(劫机) and crashes.
In a word, although flying involves danger, I would say that the advantages outweigh(在价值、意义上超过)the disadvantages. If I were asked to (30) between traveling by air and traveling by train, I would choose the former.