The book mainly deals with the trouble teens might have _____  right from wrong.  [ ]

A. distinguishing              

B. distinguished  

C. to distinguish              

D. to be distinguished

男性，38岁，突然腹痛、腹胀、停止排便排气，伴有呕吐，呕吐物为血性液体，可能的诊断为( )。

A．急性阑尾炎
B．胆道蛔虫症
C．输尿管结石
D．绞窄性肠梗阻
E．单纯性机械性肠梗阻