Please choose the correct ending to complete the given sentence: Elliptical trainer: . a woman wearing light blue tank top and black shorts

Ending1: is using an elliptical trimmer on the classroom floor near a large black mat and parallel bars on the floor. Ending2: is exercising on an elliptical. Ending3: is sitting in a seat and skis. Ending4: is standing on a roof wearing a blue automatic attack machine.

Answer format: ending1/ending2/ending3/ending4