Extracting info from one file based on the contents of another

[ichibanj]

Hi, I don't really know where to start with this query - can anyone help please?
I have three files, each with various fields:
File A - all courses available at all institutions
File B - all institutions
File C - all universities, which is a subset of File B

Is it possible to get a new file which is the same as list A, but only has courses for the universities found in list C?

Many thanks

[June7]

Do you mean you have 3 tables in 1 database file? Build a query. This is very basic Access fuctionality.

[ichibanj]

Thanks, yes I meant tables, and I realise it's probably a very newbie question, but I'm struggling. I have run queries, but I don't know how to filter one table based on the contents of another.