Wang Lin failed to be admitted by Hong Kong University last year，and only then________the importance of English.

A．he finally realized

B．he had realized

C．had he realized

D．did he realize

钼缺乏患者生化检查可见（）。

A.血蛋氨酸浓度升高

B.尿酸浓度升高

C.尿硫酸盐排出量减少

D.A+B+C

E.A+C