[不定项选择题]There are two kinds of motive for engaging in any activity: internal and instrumental. If a scientist conducts research because she wants to discover important facts about the world, that's an internal motive, since discovering facts is inherently related to the activity of research. If she conducts research because she wants to achieve scholarly renown, that's an instrumental motive, since the relation between fame and research is not so inherent. Often, people have both for doing things. What mix of motives--internal or instrumental or both--is most conducive to success? You might suppose that a scientist motivated by a desire to discover facts and by a desire to achieve renown will do better work than a scientist motivated by just one of those desires. Surely two motives are better than one. But as we and our colleagues argue in a paper newly published in the Proceedings of the National Academy of Sciences, instrumental motives are not always an asset and can actually be counterproductive to success. We analyzed data drawn from 11320 cadets in nine entering classes at the United States Military Academy at West Point, all of whom rated how much each of a set of motives influenced their decision to attend the academy. The motives included things like a desire to get a good job later in life and a desire to be trained as a leader in the United States Army How did the cadets fare years later? How did their progress relate to their original motives for attending West Point? We found, unsurprisingly, that the stronger their internal reasons were to attend West Point, the more likely cadets were to graduate and become commissioned officers. Also unsurprisingly, cadets with internal motives did better in the military (as evidenced by early promotion recommendations)than did those without internal motives and were also more likely to stay in the military after their five years of mandatory service. Remarkably, cadets with strong internal and strong instrumental motives for attending West Point performed worse on every measure than did those with strong internal motives but weak instrumental ones. They were less likely to graduate, less outstanding as military officers and less committed to staying in the military. Our study suggests that efforts should be made to structure activities so that instrumental consequences do not become motives. Helping people focus on the meaning and impact of their work, rather than on, say, the financial returns it will bring, may be the best way to improve not only the quality of their work but also their financial success. There is a temptation among educators and instructors to use whatever motivational tools are available to recruit participants or improve performance. If the desire for military excellence and service to country fails to attract all the recruits that the Army needs, then perhaps appeals to “money for collegecareer training” or “seeing the world”will do the job. While this strategy may lure more recruits, it may also yield worse soldiers. Similarly, for students uninterested in learning,financial incentives for good attendance or pizza parties for high performance may prompt them to participate, but it may result in less well-educated students. Which of the following is closest in meaning to the underlined word “cadets” in Paragraph 3? A. In-service soldiers.
B． Military researchers.
A.

B.Military officers.
C.

D.Military trainees