A、By sheltering them in a cave. B、By killing the attacking bears. C、By lifting them well above the ground. D、By taking them to t

(9)Devils Tower, the first national monument in America, could almost be mistaken for the stump of an enormous tree. Its sheer rock sides sweep up from a broad base until they cut off abruptly at the flat summit. Rising more than 1,000 feet in the middle of the gently rolling plains of Wyoming, the massive column of rock looks as though it was dropped down into this location from a different time and place.
    In a sense it was. Devils Tower is a relic of the past, when the molten rock of the earth’s core forced its way to the surface to form the throat of a volcano. As the centuries passed, the rock cooled and hardened, shrinking and cracking into long columns.(10)Born in fire and fury, Devils Tower was then shaped by the slow, gentle work of wind and water. The outer layers of the volcano were worn away, until the hard core stood completely exposed.
     (11)Small wonder that an Indian legend described Devils Tower as being formed by supernatural powers. The legend says that when seven girls were attacked by bears, they took refuge on top of a small rock, and they appealed to the Rock God for help.(12)The god caused the rock to grow and to lift the girls far above the ground, while its sides were scored by the claws of the angry bears. Even today, says the legend, the girls can be seen above the towering rock, as seven shining stars in the night sky.
Questions 9 to 12 are based on the passage you have just heard.
9. What does Devils Tower look like?
10. What caused the volcano’s outer layers to wear away?
11. What does an Indian legend say about Devils Tower?
12. How did the Rock God help the seven girls in the Indian legend?