In Spanish, 'Me dolió' is the correct form indicating 'My stomach hurt.'
Me dolió is the correct choice in this context. The verb is in the preterite tense ('dolió') indicating a specific past action of the stomach hurting after eating the bad cafeteria food.
Similarly, me is the correct reflexive pronoun which agrees with the action happening to the subject (the stomach) in the past.
Choosing 'OA. me dolió' shows the correct conjugation and agreement between the verb and reflexive pronoun in Spanish.