题目内容：

Mobile communications and the IP phone business have gradually replaced traditional long-distance calls. Mobile communications account for 28.5 percent of the total long-distance communications business. IP phones have 41.4 percent, while traditional long-distance calls are down to 30.1 percent.

China Mobile, the country's largest mobile communication operator, has accounted for nearly 40 percent of taxes in the domestic telecom market. That puts it at the top of the six major telecom operators in the nation, according to the latest official statistics. The other five are: China Telecom, 31.1 percent; China Netcom, 16.6 percent; China Unicom, 13.4 percent; China Satellite Communications Corp and China Railcom, 1.5 percent.

China Mobile is being chased by smaller rivals China Unicom and China Telecom, both of which are making significant 3G subscriber gains. That’s aided in no small part by deals to offer the iPhone. However, as of March, China Mobile did have 15 million iPhone users on its network.

In another ranking, Xiaomi, Huawei, Lenovo, vivo and OPPO came in as the top five mobile phone sellers in China by April, 2015, according to IHS Technology. The report also says that during this period, China produced 82 million handsets. (手机) (including GSM, GPRS and CDMA phones) and sold 80 million. Of the phones sold, 37 million were exported to other countries. Analysts point out that China's lack of core technologies and its heavy reliance on overseas technologies have proved to be an obstacle for development of domestic phone makers.

1.Nowadays, mobile communications have gradually taken the place of________ .

A. IP phone service

B. telecom operators

C. traditional telephones

D. traditional long-distance calls

2.The underlined word "obstacle" means________ .

A. advantage    B. puzzle     C. difficulty    D. factor

3.We can infer from the text that __     .

A. most phones are sold in foreign countries

B. most long-distance calls are made through mobile phone today

C. China had the most mobile phone users

D. China Telecom brings in more taxes of all the companies