¿con quién trabajó paula?

paula trabajas con josefina.

paula trabajaron con josefina.

paula trabaja con josefina.

paula trabajó con josefina.

The correct answer is option d) Paula trabajó con Josefina.

Explanation:

The question is highlighting who Paula worked with in the past by using the verb "work" ("trabajó") in the past tense, then the verb in the correct answer also has to be conjugated in the past tense. Moreover, there must be an agreement of number and person of the subject and the verb, so as we are talking about Paula that is it in the singular third person, then the correct answer also have to be conjugated with these characteristics.

Now, option a) trabajas is conjugated in the present simple for the singular second person, so it is not correct. Option b) trabajaron is conjugated in the past simple for the plural third person, thus it is not correct. Option c) trabaja is conjugated in the present simple for the singular fists person. And Option d) trabajó is the only one that it is correct because it is conjugated in the past simple for the singular third person.