Which of the following is a benefit to exercise

You have weighed the likely outcomes of your decision to move in with your dad and have made a decision based on those outcomes what is an example of

Mucous membranes.. a. cover or line external surface of body. b. line internal body surfaces that are in contact with the environment. c. produce antibodies to combat infection. d. secrete sweat, which has antibacterial enzymes.

First to answer will be the brainliest i need the answer asap