阅读下面材料,从A、B、C、D四个选项中选出最佳选项。Qingming, literally (字面上) means "clear and bright". It is one of the 24 seasonal division points in China. After the festival, the temperature rises and rainfall increases. And then farmers begin to grow crops. Qingming Festival falls on April 4 this year.
As a festival, Qingming is believed to have a history of about 2,500 years. The most important tradition of Qingming is to honor ancestors and remember the dead family members. So Qingming is also called Tomb-Sweeping Day. When sweeping the graves, people pray, clean the tombstones and burn offerings, usually paper money, paper clothes, paper houses and now even a paper phone.
Lots of ancient poets expressed their sad feelings with words. One of the most famous poems describing the festival was the poem Qingming by Du Mu of the Tang Dynasty as follows: A drizzling rain falls like tears on the Mourning Day;......
Some traditions of Qingming have brought such problems as traffic jams and air pollution or even forest fires. As part of a greener Qingming activity, people have been encouraged (鼓励) to pay respect to their ancestors (祖先) and dead family members online, or burn less or no paper money to protect the environment.