The answer is C. Protein is what helps your hair, skin, and nails grow.
Simply walking alone can actually do both of these however if you are looking for multiple answers then here are some examples:
-Playing Sports
-Jogging
-Lifting Weights
-Swimming
-Dancing
-Bike Riding
etc...
Anyways, hope I helped!
Answer:i would take a deep breath
Explanation: cause it relax your body to claim dowm