Choose the option where both grammar and vocabulary are c

Choose the option where both grammar and vocabulary are correct:

I. “When she did get in, Andrea could see that she was not, in fact, so little.”
II. “It was then that she noticed something worrying about the dog.”
III. “She replaced the receiver, then quickly backed out of the door and ran into the street.”
IV. “At this point I called a plumber to come and fix my drain.”