参考答案C解析:
How does the speaker view the American“Color Doctors”?
C.【精解】文中指出，维里蒂遇到的有些人显然没有科学的知识来支撑他们的观点，例如，美国的“颜色医生”认为通过运用彩色的灯光可以治愈严重的疾病。由此推断，作者对美国“颜色医生”持怀疑态度，故C)为答案。
A．It is a ldnd of social problem． B．It has a bad impact on mental health． C．It makes people less effective at work． D．It troubles most people nowadays．