HELP ?FEIFEI 131

爱睡觉的猫

131. To become an expert on a musical instrument, a person must practice. If a person practice a musical instrument for three hours each day, they will eventually become expert on that instrument. Therefore, if a person is an expert on a musical instrument, that person must have practiced for at least three hours each day.

Which one of the following most accurately describes a flaw in the reasoning above?

(A) The conclusion fails to take into account that people who practice for three hours every day might not yet have reached a degree of proficiency that everyone would consider expert.

(B) The conclusion fails to take into account that practicing for less than three hours each day may be enough for some people to become experts.

答案为什么是B. 觉得A 也对啊 ,

爱睡觉的猫

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Fangliu

A is incorrect because of "yet", if ...then is conditional reasoning, stimulus says "eventually ", so it doesn't matter that "people who practice for three hours every day might not YET  have reached a degree of proficiency that everyone would consider expert", eventually they will.

B is correct becuase "less than 3hours" is the ligic opposite of "at least 3h", B is saying, <3h---> not expert, contrapositive of this condition is expert --->at least 3h, the conclution in the stimulus.

Totally Personal.