A、Landmarks. B、Magnetic fields. C、Wind velocity. D、Climate change. B事实细节题。本题问的是讲话者谈到了迁徙类动物的哪些地理线索。短文后半部分提到，鸟类等迁徙类动物可以从一些事物中获得地理线

(22)When Holly, the house cat, turned up a mile from the West Palm Beach, Fla., home of her owners Jacob and Bonnie Richter, they were more than a little surprised to see her. After all, they had lost the cat two months ago and over 200 miles away at an RV rally in Daytona Beach.(23)And yet here was Holly— suffering from sore paws and weight loss but definitively the same cat, according to the microchip implanted under her skin.(24)While the Richters are thrilled to have their cat back, Holly’s journey has scientists completely baffled. According to the Times, there is relatively little information available on the navigational skills of cats as the issue has not been avidly studied. While(25)migratory animals like birds can take geographic clues from things like magnetic fields, cues for smell, or orientation of the sun, when it comes to cats, no one quite knows: there is little data available on the subject. "We haven’t the slightest idea how they do this," Jackson Galaxy, a cat behaviorist who hosts the show "My Cat from Hell" on the Animal Planet cable channel told the Times. "Anybody who says they do is lying, and, if you find it, please God, tell me what it is." How Holly managed her incredible trek has so far remained a mystery. "It was quite a journey for this little girl," owner Jacob Richter told a local television channel. "We just can’t believe she came home."
22. How did the Richters react when seeing Holly back?
23. What changes did the cat have when she was back?
24. What can we know about Holly?
25. What are the clues for migratory animals according to the speaker?