1. Omar y Antonio almorzaron en un restaurante mexicano.
2. Usted no puede ir al cine porque no encuentras las llaves del coche.
3. ¿Vienen ellas a la fiesta?
4. Nosotros volveremos al residencial estudiantil a las seis de la tarde.
5. Mi hermana durmió ocho horas.
They are correct, but I didn’t know if you wanted it to be written in past, present, or future.
Answer: los (choice D)
Manuela quiere a sus papás.
Manuela <u> los </u> quiere.
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Explanation:
The "los" in this case means "them". It's a plural direct object pronoun. We go with the masculine form because the singular el papá ties together with the plural los papás
The sentence "Manuela quiere a sus papás. Manuela <u> los </u> quiere" translates to "Manuela loves her parents. Manuela loves them". You could also make an argument to replace "loves" with "wants", and mean the same thing (more or less). This is because the base verb querer means "to want" and it also means "to love", among other slightly similar/related meanings. So it all depends on context pretty much.