In order for a check to be properly negotiated, it needs to be endorsed by all payees listed on the check.
The answer to this question is (c) by both payees. In order for a check to be properly negotiated, it needs to be endorsed by all payees listed on the check. In this case, the check is payable to both Gloria Schell and Pippen Tallit, so both of them need to endorse the check. If either one of them fails to endorse it, the check will not be considered properly negotiated.