Critical Reasoning (CR) | Martial artists are capable of tolerating higher levels of pain than

Martial artists are capable of tolerating higher levels of pain than an average human being. Researchers studied the blood samples of Chung Lee – a renowned martial artist – and found more than average level of endorphins – certain biological compounds that can lower the perception of pain. Based on these findings, they concluded that the higher level of endorphins is the reason for the higher pain threshold in martial artists.

Which of the following, if true, helps assess the validity of
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