单项选择题

Some 4,000 Americans ambitious to become physicians (医生,内科医生) are studying for their M. D. s abroad. Many were rejected by U.S. medical schools simply because there was no room. Last year, for example, some 13,000 of 35,000 would-be physicians who applied to U. S. schools were accepted. Of those who were turned down, well over 600 are trying the foreign route.
But gaining admittance to a good foreign school may be a problem. British medical schools give priority to Britons, and Canada’s world-renowned McGill University School of Medicine takes only a handful of well qualified Americans annually. But several schools do welcome U.S. medical students—if they can master the local language. More than 500 Americans are enrolled in the Belgian universities at Brussels and Louvain, for example. Some 800 attend the Italian University at Bologna; 175 at Rome. Mexico’s Autonomous University of Guadalajara numbers 1,300 Americans among its 4,000 students.
Despite difficulties abroad, many Americans complete their medical education, and manage to win the respect of their professors and classmates. One second-year student at Louvain has a simple explanation for these successes: "Anyone who comes here has to be motivated. You have to learn a new language, the school is constant hard work, and it’s difficult to get back into the States to practise".
Before they can become interns (做实习医师) or practise in the United States, graduates of foreign schools must pass a special examination required by the medical-education authorities. The tough test is designed primarily to weed (铲除) out those who are unable to speak English or whose medical education is not up to U. S. standards.

Which of the following can be the title of this passage()

A. Foreign Medical Schools.
B. Life at Foreign Medical Schools
C. The Tough Foreign Route.
D. American Would-be Physicians at Foreign Schools.