Which system is not directly connected to itself A) skeleton
B) Digestive
C) Endocrine

I need help, please :(

B) Digestive

Explanation:

The system is dependent in the digestive system because it sends the nutrients to the bones and this helps the bone growth and the repair. It can not be A. since the skeleton system is connected with the muscular system physically, this is to protect muscles and allow the skeletal muscles to make the bones move, so this system is connected with itself with the help of the muscular system! The endocrine is somewhat connected with the nervous system, they are both essential to the communication and response system. This eliminates A and C and leaves you with B!

i think it's c. i'm not sure but i think so.