Answer:
The correct answers are:
1.- Compramos.
2.- compró
3.- busqué
4.- compraste
5.- Ellos lo compraron
Explanation:
All right, to understand this answer we need to analyze all off them. They are finished phrases this form is called undefined preterit or perfect preterit of simple indicative. The verb is always in its undefined preterit form.
In the first case, we need to find a finished plural verb to say we bought some sunglasses. So, compramos is the correct answer.
In the second case, we are looking for a past verb about her. So compró is the correct answer.
In the third case, we are looking for a past verb about me and my action, so the correct answer is: Busqué
In the fourth case, we are looking for a past verb for singular you. So compraste is the correct answer.
In the fifth case, we are looking for a verb for plural they, so Ellos lo compraron is the correct answer.