He says he is not tired and _____ have a rest. [ ]

A. needn't

B. doesn't need

C. needn't to

D. don't need to

目前最常用于检测淋巴细胞HLA抗原的血清学方式是（）

A.补体综合试验

B.双向琼脂扩散试验

C.补体依赖的微量细胞毒试验

D.混合淋巴细胞反应

E.凝集反应