题干
控制变量法是实验探究的重要方法，下列实验方法的设计中，能达到实验目的是（ ）
A：图甲比较铁、铜的金属活动性强弱
B：图乙探究金属的锈蚀是否需要水
C：图丙探究MnO2对H2O2分解的催化作用
D：图丁探究可燃物的燃烧是否需要达到一定温度
答案(点此获取答案解析）
B
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