Yes, it's malformed. There is no expectation that (a) and (c) can be simultaneously satisfied, since they are linked by a chain of "or"s. But it seems clear that the intent of the document is that you're supposed to certify two things:

   I. At least one of (a), (b), (c) is true.

  II. I understand and agree as specified in (d).

In other words, (d) is not parallel to (a), (b), and (c) -- it's a drafting mistake to put it in the same sequence of clauses.