阅读理解
阅读下列短文，从每题所给的四个选项 （A 、B 、C 和 D ）中，选出最佳选项。
Christmastime in the city brings forests of trees already cut and waiting to be sold. But some people like to drive to tree farms. Others wait for their trees to come to them. They order one from the pages of a catalog or on the Internet. Some say the easiest thing of all is to buy a manmade tree with Christmas lights already on it. No falling needles to have to clean up.
The National Christmas Tree Association says 33,000,000 real trees were sold last year, compared to 9,000,000 manmade ones. Manmade trees generally cost more, but they can be reused. Most natural trees are cut up and recycled, but some people buy trees that can be planted.
Most Christmas trees are now grown on farms instead of in forests. Twenty-one thousand tree farmers in the United States grow Christmas trees on more than 180,000 hectares. Oregon was the leading producer last year.
Twenty-two percent of people who bought real trees last year chose them at a farm. Two percent of those people cut the trees themselves. The next most popular places were big stores like Walmart and Home Depot. Groups like the Boy Scouts also sell Christmas trees. But some people pay nothing for theirs. They steal it.
Cornell University in Ithaca, New York, has many pretty evergreens. Some years ago, a university worker found a way to keep them there. A month before Christmas, workers treated them with “pink ugly mix”. It contains water and red food colour. The bright colour starts to disappear after about a month. It can take longer, however. Cornell decided not to use the mix this year, but the idea has spread.
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