语法与词汇 Unemployment has come down slightly, but this does not _____ thefact that it is still a major problem.
【正确答案】 B
【答案解析】句意：失业率稍有下降，但这并不能改变这一事实，失业仍然是一个重大问题。alter改变。alert警告。alarm使惊恐。altar圣坛。故选项B符合句意。