If you want tocheck where the nearest coffee shop to your home is,if you want to know how toget to a place in your city,

问题描述:

If you want tocheck where the nearest coffee shop to your home is,if you want to know how toget to a place in your city,or if you want to see where in the world yourforeign pen friend lives,there's now a new free online map you can use.
Last month,Chinastarted its official online mapping service,Map World."Through this freeonline service users can fly over mountains and valleys around the world andsearch for restaurants and traffic information across the country forfree," said Xu Deming,director of the State Bureau ofSurveying and Mapping (SBSM).The Bureau,which does China's surveying and mapping work,is in charge of the Map World project.
Users can get intoMap World through www.tianditu.cn or www.chinaonmap.cn and search for 2- and3-D images from across the world.The home page shows a view of the Great Wall.
"It took abouttwo years to prepare the service with all the satellite(卫星) images taken from 2006 to 2010," saidJiang Jie,director of the database department(数据库部门)under SBSM.
The technology(技术) and website are still at an early stage.The images from inside Chinaare detailed.Users can see close pictures of roadsides.But the views ofplaces outside Chinaare less clear.
29.What is the main purpose ofthe first paragraph?
A.To show howvaluable the service is.
B.To introduce thenew online photo-map of China.
C.To show theimportance of the new online photo-map.
D.To tell howpopular the new online photo-map is in China.

选b,作者用一系列的条件句来引出文章的主题就是the new online photo-map of China.第一段就是简单的介绍了一下