下列不属于补体活化的旁路途径激活物的是()

A．细菌脂多糖

B．酵母多糖

C．凝聚的IgA、IgG4

D．肽聚糖

E．IgM

—What's the meaning of the saying whenever you fall, pick something up?  

—It tells us to___     __hope even when coming across failure; try to learn something valuable from it.    [ ]

A. look for  

B. call for  

C. take up  

D. give up