The correct option is A) They carry messages that result in a return of the system to its original state.
Negative feedback loop comes into picture whenever there is hyper secretion of a hormone which leads to the hyperactivity of any organ in the body. Excess of hormone which leads to the hyperactivity is not good for our body because it leads to wastage of energy. But, we want to conserve our body's energy from such unnecessary wastage. In order to do it, negative feedback loop is operated in which neurons and hormones carry such messages which lead to the original state of the body from hyperactive state. Excess of hormone secretion not only leads to the wastage of energy but also it can lead to diseased state which is curbed by running a negative feedback loop.
