题目内容

根据报道，某国科学家在一颗60万年前来到地球的火星陨石上发现了有机生物的痕迹，因为该陨石由二氧化碳化合物构成，该化合物产生于甲烷，而甲烷可以是微生物受到高压和高温作用时产生的。由此可以推断火星上曾经有过生物，甚至可能有过像人一样的高级生物。以下条件除了哪项外，都对上文的结论提出了质疑( )

A. 火星陨石在地球上的60万年间可能产生了很多的化学变化，要界定其中哪些物质仍完全保留着在火星上时的性质不是那么容易的。
B. 60万年的时间与宇宙的年龄相比是微不足道的，但在这一期间的生物进化的历史可以是丰富多彩的。
C. 微生物受到高压和高温作用时可以产生甲烷，但甲烷是否可以由其他方法产生是有待探讨的一个问题。
D. 由微生物进化到人类需要足够的时间和合适的条件，其复杂性及其中的一些偶然性可能是现在的人们难以想象的。
E. 题干所说的二氧化碳化合物可以从甲烷产生，但也不能绝对排除从其他物质产生的可能性。

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