E is wrong because E means " evidence provide support in order that evidence classify". This is not logic. the logic/intended meaning is "evidence provide support for someone to classify" . Am I correct in this point ?
Yes. It doesn't say a specific person will classify, but rather that support for classifying these two species separately. But your sentence makes logical sense.
Can I say that " to do " is used to show purpose of the subject of the first verb but "for doing " is used to show purpose of other persons ??? I am confused,
Different issue altogether. To + verb = the infinitive form of a verb. To + noun = prepositional phrase.