A. 3D food printing will replace traditional cooking. B. It would hurt our tradition of food culture.

　　C. The future of 3D food printing is uncertain. D. 3D food printing would be a failure.

　　28. Which of the following can be the best title for the text?

　　A. 3D food "printing": coming to the kitchen B. Can 3D printing create everything?

　　C. 3D-printing food will be in fashion! D. The disadvantage of 3D food printing

C

　　The sun is setting on a summer night. At the entrance to a deep, dark cave, a few bats fly out and begin swirling high up into the air. More and more of the small, furry creatures appear. Within a few minutes, a whole river of bats is pouring out of the cave, and they keep coming, millions and millions of them.

　　Sounds like a scary horror movie? Believe it or not, this scene takes place every night, all summer long, at Bracken Cave in Texas ,US, where 20 million bats fly outside to feed on insects."It is magical," says Jim Kennedy of Bat Conservation International in Austin Texas."It is one of the most majestic animal movements on the planet."

　　Every March or April, Mexican free-tailed bats migrate up to 1,000 miles (1,609 kilometers) from their winter home in Mexico to this cave, where they raise their young. Soon after they arrive, each mother gives birth to one pup. As many as 500 baby bats crowd into one square foot (30.48 cubic centimeters) of space, all those bodies create nice warm temperatures to keep them cozy and comfortable. If you've ever lost sight of your parents on a crowded play ground, you may be wondering how mother bats recognize their children. They use their sense of smell to tell which pup is theirs when it is time for the babies to nurse.

　　The cave, a quiet place in winter, is filled with life all summer-and not just with bat residents. Bat waste soon covers the floor, providing food for tiny organisms(生物体) like bacteria and fungi(真菌).And then there are the bugs.

　　When the adult bats leave the cave at night to feed, they are helping humans. They eat tons of insects in a single night, including many pests that eat farmers' crops. And they get rid of mosquitoes, too.

　　　29. In the first paragraph, the author 　　　.

　　　A. describes the movement of bats B. provides some information about bats

　　　C. advises the reader to watch bats D. stresses the danger of bats in summer

　　　30. According to the passage, the reader possibly thinks that　　　.

　　　A. no people know how many bats live in Bracken Cave

　　　B. bat waste causes much harm to the human environment

　　　C. a bat mother would have trouble finding her own baby

　　　D. farmers will never have a good harvest without the bats

　　　31. Which of the following is TRUE about the bats?

　　　A. They are well protected by farmers. B. They smell better than other animals.

　　　C. They benefit from some tiny organisms. D. They travel from Mexico to America yearly.

32. By saying "Sound like a scary horror movie?" what does the author mean______?

　　　A. Bats are better horrible characters in films． B. People tend to feel afraid of bats．

　　　C. The cave mentioned is full of adventure． D. The above scene is somewhat unbelievable．

　D

Growing up in one of the poorest communities with most crimes in Los Angeles, US, being