题目

As the pace of life continues to increase, we are fast losing the art of relaxation. Once you are in the habit of rushing through lift, being on the go from morning till night, it is hard to slow down. But relaxation is essential for a healthy mind and body.                               Stress is a natural part of everyday life and there is no way to avoid it. In fact, it is not the bad thing it is often supposed to be. A certain amount of stress is vital to provide motivation and give purpose to life. It is only when the stress gets out of control that it can lea _____ORBIS doctor who got here yesterday needed _______ X-ray machine to examine his patients. A. The; a           B. The; an          C. An; a            D. An; an