Dimitri went through a lot of hard work during basic training in the army. at times, drill sergeants yelled at him; he was physically exhausted and emotionally distressed. but, at the end of basic training, he felt that joining the army had been a very good decision. the self-esteem explanation for dimitris feelings about basic training is that

answer:

d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.

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