新概念英语3的几个选择题不懂,求讲解.

新概念英语3的几个选择题不懂,求讲解.
Anthropology is a science ____ anthropologists use a rigorous set of methods and techniques to document observations that can be checked by others.
A.in that B.that in
C.that D.in
（为什么不是C而是B?麻烦分析下句子）
Merurydiffers from other industrial metals ____ it is a liquid.
A.whereas B.in that
C.because of D.consequently
(引导原因状语从句的这几个词分不太清,麻烦讲一下ABD项的区别.
还有,那个in consequence of用法是不是相当于because of额?)
She did not want to go Africa,chiefly ____ the weather is too hot.
A.Because B.As C.Since D.For
(答案选A,为什么?为什么不是B、C?)
____we are all here,the meeting can begin.
A.With B.In that C.For D.seeing
(为什么选D而是不B?)