Aperson touches a hot surface with his hand and his hand springs back. which two systems are operating?

The answer to this question is letter A.nervous system and musculoskeletal system   

When  person touches a hot surface with his hand and his hand springs back. His nervous system and musculoskeletal system   is operating. 

A.nervous system and musculoskeletal system   B.cardiovascular system and endocrine system    C.musculoskeletal system and endocrine system  D. nervous system and cardiovascular system

The answer is nervous and musculoskeletal system.

When a person touches a hot surface with his hand, a receptor detects a stimulus. The information is sent to relay neuron through a sensory neuron, parts of nervous system. Relay neuron sends information to the effector (musculoskeletal system) through a motor neuron and effector produces a response.