Query where data appears in more than one column

Hi,
I'm looking for help with an Access query to return a data contained in one table from another table where it could appear in two columns but with duplicates removed.

Check_tbl

ID C
1 123
2 456
3 789
4 FDFHSFHGF
5 SDFGDGFDS
6 ABC

source_tbl

ID A B F
1 123 ABC 156.pdf
2 456 440.pdf
3 DEF 149.pdf
4 789 GHI 160.pdf
5 111 178.pdf
6 JKL 506.pdf
7 156.pdf

I need the query to return every entry in check_tbl.C which appears in source_tbl.A and source_tbl.B as well as source_tbl.F but I need duplicates removed where check_tbl.C appears in both source_tbl.A AND source_tbl.B (ie only return one of the two results)

Returned result should look like this:

results

C F
ABC 156.pdf
456 440.pdf
789 160.pdf

since value 123 and ABC from check_tbl.C appear in source_tbl.A and source_tbl.B respectively, only one is returned.

If anyone can assist with this I would be grateful.