A、Half an hour. B、Fifteen minutes. C、Twenty minutes. D、One hour. B文章最后论述，政府有意兴建渡船计划。另外，还有一项提议就是开发15分钟之内就能够到达的渡船 (make the trip w

The golden gate bridge joins the beautiful city of San Francisco with the suburbs to the north. Each day, about one hundred thousand automobiles cross the bridge, taking people to and from the city. More than haft of them cross the bridge during the morning and evening rush hours; with traffic so heavy, the trip is not pleasant. (29) Now, however, there is at least one group of happy commuters. These are the people who travel under the bridge instead of on it. They go to work by boat and enjoy it so much that most of them say they will never go by car again. The ferry they take is the roomy quiet, comfortable" Golden Gate". Commuters can enjoy the sun on deck. In the morning, they can have breakfast in the coffee shop, and in the evening they can order a drink in the bar while looking at San Francisco’s famous skyline and the nearby hills. The trip takes only thirty minutes and is not very costly. But best of all, being on a boat seems to make people feel more friendly toward each other. There has already a marriage of two commuters who met on the "Golden Gate". (30) Since the ferry has been so successful, there are plans to use other, still, larger boats. (31) There is also a proposal for a high speed boat that will make the trip within only fifteen minutes. Not everyone is happy about that. A lot of people don’t want to get back and forth faster; they feel that half an hour is just enough time to relax.