24.This is the microscope ______ which we have had so much trouble.A) at B) from C) of D) with为什么是D呢,of不行吗

of 是先行词指人的时候用，with 是先行词指物的时候用

此题考查固定搭配和定语从句。
which作为关系代词，等同于先行词the microscope，放入定语从句中为：
with which we had so much trouble
= we had so much trouble with which
= we had so much trouble with the microscope
此句含有固定搭配：have trouble/difficulty with sth，意思是“在某事上有麻烦/困难”。

have trouble with sth.在...方面有麻烦，是固定短语。
the microscope是先行词， with which we have had so much trouble.是修饰它的定语从句。
which指代the microscope，
正常的短语是have trouble with the microscope，意思是在使用这台显微镜上有麻烦

of 表示所属关系
with 表示包含

have trouble with sth.
如：They have some troubles with the machine.
他们的机器出问题了.
这句话说的是,这就是我们出了很多问题的microscope.先行词which指代microscope.因此用with.