Which is correct? At the Greens' or at the Green's?

---Where is Tom?
---At ____________.
A. the Greens' B. the Green's

I am not sure about the choice. Would you please help me? Thanks a lot.

b

The apostrophe indicates possession. If "the Green's" is short for the Green family's house, then it would be B because they possess the house and Green is singular (their name is Green without an 's' at the end).

If it was a restaurant at a golf course called "The Greens," then it would not have the apostrophe because there's no possession. That's the entire name.

If you're referring to the resturant's lawn mower however, since The Greens is plural (followed by the 's') and they possess the mower, it would be written, The Greens' lawnmower. That would be A.