题目

The winner of the race is tall and thin; he ___be my friend, Mike, who is short and fat. A. might     B. mustn't      C. can't            D. should 答案：C 解析: 略欲将蛋白质从水中析出而又不改变它的性质，应加入  （   ）A．(NH4)2SO4溶液B．酒精溶液C．Pb(NO3)2溶液D．NaOH溶液