Answer:digestive system, muscular system, and skeletal system
Step-by-step explanation:
In order for your body to stand up and walk up right you need the skeletal system. the bones keep the bodies structure so the muscular system can make your body walk.The muscular system ables the body to move and to eat a apple and walk you need certain muscles to work together. Lastly you need a digestive system to actually consume the apple properly.