单项选择题

RNA的碱基中不包括（）

A．腺嘌呤
B．胸腺嘧啶
C．鸟嘌呤
D．尿嘧啶

<上一题目录下一题>

热门试题

未分类题

The actual production and comprehension of the speech by speakers of a language is called ______.A.grammar rulesB.competenceC.performanceD.language device

A.A.grammar
B.competence
C.performance
D.language

未分类题

According to Saussure, the relation between the signified and the signifier is arbitrary.

相关试题