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| 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. The leguminous plants—among
 5 them crop plants such as soybeans, peas, alfalfa, and
 clover—have solved the nitrogen supply problem by entering
 into a symbiotic relationship with the bacterial genus Rhizobium.
 
 
 10. Which of the following situations is most closely
 analogous to the situation described by the author
 as one of nature‘s great ironies?
 (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 shipwrecked sailors at sea in a
 lifeboat, with one flask of drinking water to
 share among them
 (D) That of a motorist who runs out of gas a mere
 five miles from the nearest gas station
 (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
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