Healthy activities such as biking and swimming appeal most to me. It is good to do several of these activities because they are beneficial to your body, as long as you aren’t working it out too much.
It is true, since there really is no way to explain it, look at the picture below.
https://www.google.com/url?sa=i&source=images&cd=&ved=2ahUKEwjbm6jyusLeAhVC2VMKHTHUCnEQjRx6BAgBEAU&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FMyPlate&psig=AOvVaw1MJ9CiEdM-NRdRHxX4N2qV&ust=1541686191832175
True. Lactic acid is caused by strenuous exercise. The lactic acid is formed because while working out, you don't receive as much oxygen.
C. Muscle sprain
I think would be the answer