Carter has recently become interested in the martial arts because of their self-defense benefits. He has written an essay to convince his friends and family members to join martial arts classes so that they will be more capable of self-defense. The opening sentence in his essay is Martial arts classes will benefit almost anyone. Which of these is a CLEAR improvement of his opening sentence? A) Learning martial arts is something that I believe everyone should do. B) People who take martial arts classes gain a lot of important knowledge. C) Martial arts classes will teach everyone important skills that they can use. D) Taking martial arts classes helps people gain important self-defense skills.