C

　　Bats often appear in movies and literature as frightening creatures. The animals have even been linked in some cultures to vampires（吸血鬼), seeking to attack humans and drink the blood of them. In reality, bats are usually not harmful to people. They can do good things for people and the environment. For example, bats eat a lot of different insects that can harm our environment. They can also spread seeds.

　　 But a serious disease is currently threatening the bat population in many parts of the United States.The disease is called white－ nose syndrome（白鼻综合症）.It has killed more than 6 million bats across the United States since 2007. Bats catch the disease through their skin while resting on the walls of mountain caves. Biologist Lindsay Rohrbaugh says the disease spreads quickly and can lead to strange behavior in bats.

　　 In Washington D. C, researchers are studying how white-nose syndrome is affecting the area's nine species of bats. Some scientists are trapping bats on an island in the middle of the Anacostia River to test for the disease. The group is receiving money to help carry out their studies. Marco Carvello is with the Washington D. C. Government's Department of Energy and Environment. "Scientists are concerned that the disease is continuing to greatly reduce the bat population. The bat deaths are affecting the quality of human life in many ways. Without bats, there is an increase of many insects. And that's only going to get worse over time if some way can't be found. "he said.

　　One theory is that some bats are no longer returning to caves to avoid getting sick. This means more of them are now making their way into cities, where contact with humans is more likely.Experts advise people to keep away from bats incase they have the disease. And animal control officers should safely remove the animals.

28. According to Paragraph 1, people tend to think bats_______________.

A. should be protected

B. can help spread seeds

C. do harm to human beings

may damage the environment