Question 1
A. Because they found lines of minerals which would require water to be created.
Because they found that life once existed on Mars.
C. Because they found freely flowing liquid water under the surface.
D. Because they had found evidence of life on Mars.
Question 2
A. There used to be more water on Mars than in Earth’s Arctic Ocean.
B. Mars used to be covered with water more than a hundred meters deep.
C. Nearly all the water on Mars has evaporated into space.
D. Evidence of water on Mars has never been found before.
Question 2
A. They were heading back home.
B. They were celebrating New Year’s Eve.
C. They were watching fireworks.
D. They were racing to the skyscraper.
Question 3
A. Because they were putting out the fire.
Because they were rehearsing the fireworks now.
C. Because they were on New Year’s duty.
D. Because they were putting down a riot.
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