Please choose the correct ending to complete the given sentence: Finance and Business: [header] How to prevent repetitive stress injury [title] Sit comfortably at your desk. [step] Correct posture and keyboard techniques can reduce the strain to your muscles. Properly position your body on the chair so you won't need to adapt your wrists and hands to the keyboard by bending them in awkward positions.

Ending1: [substeps] Sit up straight and find your center of balance. There, you can place your right hand on the top of the keyboard, your right hand on the handle, and your left hand on your right thigh. Ending2: [title] Place both feet flat on the floor and sit upright in your chair. [step] Keep your knees at or close to the same level as your hips with leg muscles relaxed. Ending3: [substeps] Stand facing a wall and hold onto a chair with a slight bend in the elbow. Fold your elbows at your sides, at 90 degrees, so the parts of your head that are raised are the front and back of your head. Ending4: [substeps] Try one of two things: lean your hand over your keyboard or sit up straight in a chair that opens from the waist. Note which wrist position feels good and which one feels uncomfortable.

Answer format: ending1/ending2/ending3/ending4