Which disorder keeps a person from functioning normally due to intense fear? anxiety disorder

schizophrenia

personality disorder

mood disorder

Please give explanation so I understand why you say its that answer "I took the test" with proof will also do

The person who utilize the progression principle will keep adding the difficulty of the exercise that he's doing, while the person who does not, will only stay stagnant.  the person that utilize progression principle, will get a stronger endurance because now his body is conditioned to do harsher routines.{the answer was already on verified)