A、50% of those clubs B、65% C、75% D、95% C此题很简单，原文直接给出于“75%”的数据。

Ladies and gentlemen, I am glad that we are together to understand the power of yoga. Nowadays, movie stars do it; sports stars do it; even judges in the highest courts do it: that yoga thing. A path to entertainment that winds back 5,000 years in its native India, yoga has suddenly become so hot, so cool, so very this minute.
    In America, people rush from their high pressure jobs and tune in the authoritatively mellow voice of an instructor, gently urging them to solder a union between mind and body. 15 million Americans, include some form of yoga in their fitness regimen, 75% of all US health clubs offer yoga classes.
    Yoga relaxes you, and by relaxing, heals. When you do yoga -- the deep breathing, the stretching, the movement that release muscle tension, the relaxed focus on being present in your body -- you initiate a process that turns the fight, or fight system off and relaxation reponse on, that has a dramatic effect on the body.