Block 22 specifies that only one of the listed conditions may be included on a single claim.

• A. Any combination of conditions may be listed
• B. Two conditions may be listed per claim
• C. Only one condition may be listed per claim
• D. The block is optional

Answer: (C)

The rule being tested is the way Block 22 is used on the CMS-1500 claim form: it is designed to tie the service to a single diagnosis. Because the claim system is built to map each billed service to one specific condition for clear adjudication, only one condition may be listed in that block per claim. If multiple conditions could apply, they should be handled through separate claims or as allowed by payer guidelines, so that each service line has a straightforward diagnostic link.

So the correct statement reflects this one-diagnosis-per-claim limitation. Listing multiple conditions in the same block would create ambiguity for payment processors, and making the block optional would ignore its intended function.