You place a slip leash and collar on a dog, carry the dog to an examination table, and hold the dog in the appropriate positions for examination and treatment. what restraint type have you avoided?
a. manual restraint
b. chemical restraint
c. mechanical restraint
d. none; you've employed them all.

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.

i truly dont know the answer wait i do its 1,3,4