【单选题】短文 3 It is one of nature’s great ironies that the availability of nitrogen in the soil frequently sets an upper limit on plant growth even though the plants leaves are bathed in a sea of nitrogen gas....
A.
That of a farmer whose crops have failed because the normal midseason rains did not materialize and no preparations for irrigation had been made.
B.
That of a long-distance runner who loses a marathon race because of a wrong turn that cost him twenty seconds.
C.
That of a motorist who runs out of gas a mere five miles from the nearest gas station.
D.
That of shipwrecked sailors at sea in a lifeboat, with one flask of drinking water to share among them.
E.
That of travelers who want to reach their destination as fast and as cheaply as possible, but find that cost increases as travel speed increases.