正确答案： B

解析：
题目中的“the key point”与录音中提到的“high Oil their agenda”是同义表达，由此可知，改变投票体系是阿拉伯联盟会议讨论的重点，所以本题应选B。
【录音原文】
　　Meeting at the Arab League headquarters in Cairo, Egypt, on December 29th, delegates representing all 22 members began discussing a 13-point reform program approved at last year’s summit in Tunisia. High on their agenda was the need to change the Arab League’s voting system from one that requires unanimity to a two-thirds majority. Historically, the unanimity policy has prevented the Arab League from passing resolutions to deal with security issues, mediation efforts, sovereignty and attacks on Arab states, such as Iraq’s invasion of Kuwait in 1990. The charter of the Arab League, established by seven states in1945 to ensure a better future for all Arab countries, forbids any member country from using force against another member. Following the invasion of Kuwait by Iraq, a founding member of the Arab League, many critics questioned the relevancy of the Arab League. Its former Ambassador to the United Nations, Clovis Maksoud, resigned in protest.
Questions 1 to 2 are based on the conversation you have just heard.
1. How many members are there in the Arab League?
2. What was the key point discussed during the meeting?