Both of Mrs. Bailey's arms are in casts. She cannot use her hands. She asks you for a drink of water. You set the cup in front of her, but she looks at you. What should you do

U you could put a straw in the cup for her...?

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.