Among the many open research questions on MTBE are how it is metabolized, ______the levels of exposure in the general population

admin2011-01-26  39

问题 Among the many open research questions on MTBE are how it is metabolized, ______the levels of exposure in the general population are.

选项 A、but what
B、and what
C、but how
D、and why

答案B

解析 需要 what 从句结构。
转载请注明原文地址:https://kaotiyun.com/show/y9BO777K
0

相关试题推荐
最新回复(0)