Final answer:
The correct preterite form of the verb 'ir' is 'fuimos'.
Step-by-step explanation:
The correct preterite form of the verb 'ir' in this sentence is B. fuimos.
El sábado pasado, mis amigas y yo fuimos a un concierto de salsa.
The preterite form of 'ir' is used to describe a completed action in the past. In this case, the sentence is referring to an event that happened in the past, so the preterite form 'fuimos' is used.
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