Question

Which complex sentence shows correct subject-verb agreement?

My library books, which I borrowed last week, is overdue.
Salif and Peter, his teammate, practices before and after school.
The tree, which was one of the tallest redwoods, were hundreds of years old.
Her cats, which she adopted from a shelter, are fun to play with.

Answer 1

Her cats, which she adopted from a shelter, are fun to play with.

Only this is correct. other are wrong