The correct option is
A A - neural system, B - endocrine system
Early philosophers like Hippocrates believed in the good humor hypothesis, for a healthy body and mind a balance of four humors are required. But in modern days biology states that the mind influences our immune system through the neural system and endocrine system which maintains health.
Endocrine system : A messenger system present in our body, possesses glands which produce the chemical messengers called the hormones. A balance in the amount of hormones is required for proper health and proper communication between different organs. Example : Insulin and glucagon produced by the pancreas gland maintain the blood sugar level.
Neural system : A system consists of the brain, spinal cord and nerves which helps in coordinating the behaviour, functioning of different organs and coordinations in our body.
Cardiovascular system : A system of heart and blood vessels helps in the circulation of gases, nutrients and removal of waste materials in the body.
Excretory system : A system consisting of kidneys and associated organs helps in the removal of waste materials from the body.