题目内容：
What do we learn about the space-tourism firm Virgin Galactic? A．It has just built a craft for commercial flights.
B．It has sent half a dozen passengers into space.
C．It was about ready to start regular business.
D．It is the first to launch "suborbital" flights.
参考答案：【答案仅供学习，请勿对照自行用药等】
答案解析：