Which of the following phonetic transcriptions is right for the “cold”?
A：/kold/
B：/kəud/
C：/kod/
D：/kəuld/
南北半球的分界线为（ ）
The Shenzhou IX spacecraft returned to the earth safely _______ June 29th, 2012.
用分子的知识解释下列现象，正确的是（ ）
