Mi amiga elisa y yo con ropa atlética. a. vestirnos b. se visten c. nos vestimos

C. It’s talking about what they are describing in current state. This is correct because It translates to “My friend Elisa and I dress in athletic clothing”

As for answer B. It’s talking about it in 3rd person, so it translates to “My friend Elisa and I they dress in athletic clothing.”

And finally A. Is talking about future tense and can’t really be translated.

Your answer is correct