Involves speaking about sensitive subjects in a gentle way so as not to give offense.
tact
clarity
courtesy
accuracy

Tact

Explanation:

This word refers to the ability to avoid hurting poeple's sensibility by upsetting or offending them. Specially when speaking of some specific or controversial subjects a person with tact is able to say what he wants maintaining good relations with the others.

An example would be: There has been an accident in which people died.

Two newspapers report the event. One with tact, trying to give just the neccessary information and not showing anything that could affect the family of the deceased. Other newspaper reports the event without care, showing photos and appealing to the audience's morbidity, without tact.

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.

b) the bill goes to the president.

hope this