A、It happens every year. B、It was caused by long periods of rainfall. C、It is the biggest one in at least 70 years. D、It has cau

A bear was shot dead after it escaped from an enclosure at a zoo in western Germany on Friday, authorities have said. Earlier authorities said two lions, two tigers and a jaguar had escaped from the zoo, but officials later clarified that the big cats had never left their enclosures. Police had advised residents to remain indoors. While the warning was still active on the police website Friday afternoon, a spokesperson for the police clarified that the bear was the only animal at the park to break free.
Marc Potzsch, a spokesperson of the district’s disaster management organization— which is made up of police and fire brigades— said the bear had managed to leave its cage after a heavy downpour early Friday morning. The high rainfall had caused zoo cages to flood and authorities had initially been unable to verify the whereabouts of cats, sparking fears of a mass breakout. In reality, the animals had climbed to higher spots that were not visible from outside the cages, Potzsch said. The cages were being checked by structural engineers to determine whether the animals can stay remain inside their enclosures or have to be placed in more secure places, he added.
There hasn’t been a flood like this here for at least 70 years, Yannick Becker, who lives just over a mile from the zoo, told CNN. He said he had heard from the fire department that two storms had collided to cause unusually high levels of rainfall. “As far as I know, a dam broke in the zoo, which caused the area to be flooded,” he added.
Questions 16 to 18 are based on the passage you have just heard.
16. How many dangerous animals have escaped from their enclosures?
17. What does Yannick Becker say about the flood?
18. What can we learn from the end of the talk?