A、Breathing and moving smoothly. B、Concentration and breathing. C、Flexibility and breathing. D、Meditation and comfort. A短文中提到，As

We have tended to view Yoga as a kind of foreign religious exercise but in fact from a medical standpoint, the age-old set of exercises known in the West as "yoga" offers a significant variety of health benefits. It increases the efficiency of the heart and slows the respiratory rate, improves fitness, lowers blood pressure, promotes relaxation, reduces stress, and allays anxiety. It is not, in itself, a cure for any medical ailment. A typical session includes three disciplines: breathing exercises, body postures, and meditation. You may also be given advice on nutrition and lifestyle. Each session usually begins with a set of gentle warming-up exercises. The teacher will then ask you to focus on your breathing, and may take you through several breathing exercises. At the very last, you will be asked to breathe through your nose, evenly through both nostrils.  Then it’s on to the yoga postures, a series of poses that typically must be held for periods of a few seconds or several minutes. As you assume the various postures, you will be asked to move gently,  without jerking or bouncing.  Breathing techniques remain important. You will need to focus on exhaling during certain movements and inhaling during others. Likewise, as you hold certain postures, you may be instructed to inhale through one nostril and exhale through the other. You will be allowed to rest after every three or four postures, and at the conclusion of the exercises, there is usually a period of rest or meditation.