何种原因导致自体造血干细胞移植后血液系统恶性肿瘤复发率高于异基因造血干细胞移植()

A．预处理后仍残留肿瘤细胞

B．缺乏GVHD

C．移植物被肿瘤细胞污染

D．缺乏抗肿瘤效应

E．以上均是

Given that the information on the three bonds below is at issuance, which of the following choices correctly identifies the bonds as premium, par, and discount.

Bond1 Bond2 Bond3()

A. premium par discount

B. discount premium par

C. par premium discount