题目内容：
The Mysteries of Nazca In the desert of Peru, 300 kilometers from Lima, one of the most unusual artworks in the world has mystified (迷惑)people for decades. (46) But from high above, these marks are huge images of birds, fish, seashells, all beautifully carved into the earth.
The Nazca lines are so difficult to see from the ground that they weren’t discovered until the 1930s, when pilots spotted them while flying over the area. In all, there are about 70 different human and animal figures on the plain, along with 900 triangles, circles, and lines.
Researchers have figured out that the lines are at least 1,500 years old, but their purpose is still a mystery. (47) However, it would probably be very tricky to land a spaceship in the middle of pictures of dogs and monkeys.
In the 1940s, an American explorer named Paul Kosok suggested that the drawings are a chronicle (记录) of the movement of the stars and planets. (48)later，an astronomer tested his theory with a computer, but he couldn’t find any relation between the lines and movements in space.
Another explanation is that the lines may have been made for religious reasons. British researcher Tony Morrison investigated the customs of people in the Andes Mountain and learned that they sometimes pray by the side of the road. It’s possible that in the past, the lines of Nazca were created for a similar purpose. (49) But the local people have never constructed anything this big.
Recently ,two other scientists, David Johnson and Steve Mabee, have speculated that lines could have been related to water. Nazca is one of the driest places in the world and receives only 2cm of rain every year. While Johnson was searching for ancient water sources in the area, he noticed that some waterways built ancient people were connected with the lines. Johnson believes that the Nazca lines are a giant map of underground water in the area. (50)
请在（46）处填写正确答案。 A．He called Nazca “the largest astronomy book in the world”
B．Seen from the ground, it looks like lines scratched into the earth.
C．Scholars differ in interpreting the purpose of the designs.
D．Other scientists are now searching for evidence to prove this..
E．A Swiss writer named Erich von Daniken wrote that the Nazca lines were designed as a landing place for UFOs
F．The largest picture may have been the sites for special ceremonies.
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