Answer:
to Smith only, or Jones only, or Smith and Jones
Explanation:
In this specific scenario, a proper indorsement of the check would be to Smith only, or Jones only, or Smith and Jones. That is because a check needs to be as specific as possible and cannot have various options. The check needs to be made to a single specific individual and if it is for more than one individual then both need to be included as a requirement (and). Making it so that both recipients must cash the check together for it to be accepted.