Math teacher: Teaching students calculus before they attend university may significantly benefit them. Yet if students are taught calculus before they are ready for the level of abstraction involved, they may abandon the study of mathematics altogether. So if we are going to teach pre-university students calculus, we must make sure they can handle the level of abstraction involved.
Which one of the following principles most helps to justify the methematics teacher's argument?
A. Only those who, without losing motivation, can meet the cognitive challenges that new intellectual work involves should be introduced to it.
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A is the answer. Personally dislike "without losing motivation". I think it is redundant.