Hich of the following is true about protein and supplements in diets? a. everyone needs additional protein in their diet. b. weight lifters need to include supplements in their diets. c. it is uncertain whether many dietary supplements are effective. d. most supplements are known to enhance the benefits of weight training.

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)