For a sentence like this:

Copy of education credential, transcripts or proof of enrolment at a post-secondary educational institution

Does that mean

1. A and (B or C)
2. (A and B) or C
3. A or B or C

or others?

Notes: I'm not asking if there should be a comma before 'or'. Instead I want to know what does the comma imply, 'and' or 'or'.