The answer to your question will be C
9. Elena y Silva se vistieron muy bien anoche.
10. Ayer, nosotros fuimos a un restaurante
Answer: Alto
He is a boy so it ends with O
Note:
I will also add the list for correct version for the ones that aren't
Answers:
1st. None of them, you should check if there's a typo somewhere
2) Yo hago
- tu haces
- nosotros hacemos (nosotros hagamos is actually a correct conjuagation but i believe that it is too advanced at the moment seeing what this is)
- ellas hacen
3) Yo prefiero
- tú prefieres
- nosotros preferimos
- él prefiere
4) Tú tienes
- ella tiene
- ellas tienen
- yo tengo
5) Él camina
- tú caminas
- yo camino
- nosotros caminamos (this one is also correct but same reason as before)