By industry, I don't mean______usually thought
of when that word is associated with companies
and industries.
A.what is B.that we C.all
这道题选什么？这道题什么意思？

选A. what is

By industry, I don't mean what is usually thought
of when that word is associated with companies
and industries.

翻译（意译了）：“我说的“industry”(产业），并不是指通常说的公司和工业厂家。”

mean 后需要个宾语，同时后面的定语从句要个关系代词引领。这里what(=the thing that)含有这双重含义在里面。

前面的by industry 可能是个“拦路虎”的难点。给你个例句看看这个by 的用法，你就会明白了。

例：A: I really don't know if I am going to be there.
B: What do you mean by that?

“A: 我真不知道(到时）我会不会在那里。
B:　你这么说什么意思？”

这里的by industry 是同样用法。　

词组"be associated with": “和....有关系（有联系）,和。。。有关”的意思。 这里的the word这个字眼是被人们和什么什么联系起来的，所以用被动 is associated with ...。

associate单词例句： He doesn't associate with those people. 他不和那些人来往。