A new study by the Development of Health in Taiwan shows that more than half of the adult

population in Taiwar lacks an understanding of health problems.More than 2, 000 adults took part in the survey to find out about their knowledge of diet, health-care, disease control and medicine. Surprisingly, only 51% of the people surveyed understand that common cold has no cure, and taking medicine is absolutely no use at all. The problem is made worse by doctors who give their patients large doses of useless drugs. More than two - thirds believe that it is only the nicotine in cigarettes rather than the other chemicals that causes cancer. These people believe that if they smoke "light" cigarettes with less nicotine, they will not get cancer. Since 26 percent of Taiwanese adults smoke, such a misunderstanding will lead to more illness, suffering, and early death.

But the outlook for health education in Taiwan is not all negative. The survey concludes that younger Taiwanese have a better understanding of health concerns than their parents, while senior citizens have the least understanding among the three age groups.

The purpose of the survey is to find out______.

A．why people neglect their health

B．what people know about health

C．when to provide health education

D．who is more likely to become ill