I can’t help you with this
The answer is (usted) because you dont have a personal relationship with this person.
ustedes means you guys
vosotros means all of us
tu is used for someone whom you are close with like a family member or someone whom you have know for a while.
The correct answer is B, van a.
The literal translation reads, “My sister and you are going to go fishing this afternoon,” and van a means going to.
I hope I helped!
