In the developing nations, the technology has the capacity to reach teachers in remote and educationally ______ areas and hopefully improve teaching skills and productivity.

A．defective

B．efficient

C．deficient

D．effective

通常所说的SNP包括（）

A.由单个碱基的缺失所致

B.单个碱基的颠换所致

C.以上都不对

D.单个碱基的转换所致

E.由单个碱基的插入所致