【正确答案】
B
【答案解析】[听力原文]
The health benefits of exposing skin to sunlight may far outweigh the risk of developing skin cancer, according to scientists. Edinburgh University research suggests sunlight helps reduce blood pressure, cutting heart attack and stroke risks and even prolonging life.
UV rays were found to release a compound which lowers blood pressure.
Researchers said more studies would be carried out to determine if it is time to reconsider advice on skin exposure. Heart disease and stroke linked to high blood pressure are estimated to lead to about 80-times more deaths than those from skin cancer in the UK. Production of the pressure reducing compound is separate from the body"s manufacture of vitamin D, which rises after exposure to sunshine.
Researchers said that until now vitamin D had been thought to solely explain the sun"s benefit to human health.
During the research, researchers studied the blood pressure of 24 volunteers under UV and heat lamps. In one session, the volunteers were exposed to both the UV rays and the heat of the lamps. In the other, the UV rays were blocked so that only the heat of the lamps affected the skin. The results showed that blood pressure dropped significantly for one hour following exposure to UV rays, but not after the heat-only sessions. Scientists said that this suggested it was the sun"s UV rays that lead to health benefits.
The volunteers" vitamin D levels remained unaffected in both sessions.
The study will be presented in Edinburgh at the world"s largest gathering of skin experts.
What can be learned from Edinburgh University"s research?
[解析] 短文指出，根据爱丁堡大学的最新研究，日常照射可以降低血压，减少心脏病和中风发作的可能，甚至可以延长寿命，这是因为UV rays were found to release a compound which lowers blood pressure. 即UV光有助于降低人们的血压。因此答案为选项B。