THE ROOM WAS COLD. THEY LEFT THE DOOR OPEN. A. IF THEY HADN’T LEFT...

18. The room was cold. They left the door open. A. If they hadn’t left the door open, the room wouldn’t have been cold. B. The room wasn’t cold because they didn’t leave the door open. C. If they didn’t leave the door open, the room wouldn’t be cold. D. If they hadn’t left the door open, the room wouldn’t be cold.  Choose the underlined part among A, B, C or D that needs correcting