Q:Write a multi-choice question for the following article, with the given choices and answer: Article: Beijing--(13, July) China sent up a new data relay satellite , Tianlian I-02, on Monday at the Xichang Satellite Launch Centre in South-western Sichuan province.The new satellite will promote the country's satellite communication network for space docking . The satellite was launched on a Long-March-3C carrier rocket at 11:41 p.m., sources at the centre told Xinhua News Agency.The satellite separated from the rocket 26 minutes after its launch and was then successfully delivered into a geostationary transfer orbit . Developed by the China Academy of Space Technology under the China Aerospace Science and Technology Corporation, the satellite is the country's second data relay satellite.The first, Tianlian I-01, was launched on April 25.2008. The two satellites will form a network to improve communications between China's spacecraft and bases on Earth, according to the centre.They will also be used to help the nation's first space docking, scheduled for the second half of this year. As planned, China will launch space module Tiangong-I, which was designed as a platform that will dock with an unmanned spaceship, Shenzhou, for the county's first space-docking mission this year. Two more Shenzhou spaceships will dock with Tiangong-I next year, and one will be manned by two or three astronauts, according to China Manned Space Engineering Office, which was the main user of the Tianlian I series data relay satellites. "The new satellite can cover a greater area to track and command the country's space vehicles in low-Earth orbits, such as manned spacecraft and remote sensing satellites, from a higher position in outer space.Only three satellites of this kind are needed to form a global communication network, and China has two now." Pang Zhihao, a researcher and deputy editor-in-chief of Space International, said. The satellite could also equip astronauts with real-time communications, which will benefit the country's future manned space flights, he said. Options: A To test the function of a Long-March-SC carrier rocket. B To carry some astronauts into space to do some research. C To send more information and clearer pictures to mobile phones on the earth. D To promote the country's satellite communication network for space docking. Answer: D To promote the country's satellite communication network for space docking. Question:
A:
What is the main purpose to send up Tianlian I-02 ?