Chronic hepatitis is usually caused by:
drug abuse
sexual contact
viral infection or autoimmune disorder
streptococcal infection

Ibelieve the answers are a and c.

Ci want to say is right

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)

Awould be the answer