四六级考试

试题来源：专业四级-186
【单选题】 _________, ozone levels in the ionosphere appear to have dropped recently.
A．However the reason
B．It is the reason
C．What is the reason
D．whatever the reason

参考答案：D
网考网解析：
[汉译] 不管原因是什么，电离层中臭氧的含量的确是减少了。 [注释] 连接副词“whatever”=“regardless of”。例如：1．He wore antique clothes and，whatever... 查看试题解析出处>>