硒中毒者头发脱落，指甲变形，严重者可导致死亡。

军事高技术分为哪几大技术群？

Some of the students _____ from Canada.[ ]

A. is

B. are

C. was

When an organism is completely encapsulated and preserved, it becomes a fossil, therefore turning into evidence of things that once lived.

A．thereby

B．as a result of

C．so

D．in the end

患儿，男，1岁。因“躯干、四肢出现红斑、水疱、糜烂3天”入院。皮肤科情况：躯干、四肢大小不等的片状红斑、松弛性水疱、糜烂面，口周见放射状裂纹，口腔黏膜无损害。该患儿最可能的诊断是

A．寻常型脓疱疮

B．脱屑性红皮病

C．葡萄球菌性烫伤样皮肤综合征

D．非金葡菌所致的中毒性表皮坏死松解症

E．Steven-Jonson综合征

、可变分区管理方式常用的主存分配算法有：______、______和______。