Which of the following is true?
a controllable risk factor for disease is family history of heart disease.
b controllable risk factor for disease is race.
c controllable risk factor for disease is age.
d controllable risk factor for disease is eating a nutritional diet.

D. You are able to control your food intake, ensuring you are eating a healthy and well balanced diet to reduce the risk of diseases and illnesses.
You are not able to change factors such as your genetics, age, or race.

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)

Your answer is d. recognition! hope this