51单片机中断允许寄存器为

A.04
B.04
C.04

听力原文：America’s universities are the envy of the world with 60% of all U.S. high school graduates attending college, while in Germany, it’s 30% in France, 28% and in Britain, only 20%. （）A．Thirty percent of the German population can receive college education．B．American students enjoy a very high rate of admission to college in the worlDC．Comparatively speaking, there are more British people than the French attending collED．American college students are envied by 60% of high school graduates around the worlD．