Answer:
un bocadillo
Step-by-step explanation:
It can't be una ensalada because that is a salad. It can't be unas papas fritas because that is french fries. It can't be unos vegetales because that is vegetables. It can't be un pan dulce because that is sweet bread. It can't be un te helado because that is a cold tea. It cant be la cena because that is dinner and a ham and cheese sandwich is not a whole meal. And lastly, it can't be unas frutas because that is fruit. Therefore, the only correct answer would be un bocadillo. Hope this helps! If you need anything else with regards to spanish let me know. I'm fluent :)