In general, which factor is not critical when beginning an exercise program?

B. finding friends who like to exercise the same way you do. Although that is a good thing, because that increases the chances to continue exercising after some months, it is not a requisite, because you can exercise alone or you can make new friends at the exercise place chosen by you. On the other hand, it is very important that you use appropriate protective equipment, seeing a doctor for a physical assessment prior to beginning exercise, and choosing clothing that matches your program.

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)

Think it's rice because in many countries rice is the main food so it can be traditionally served all at once.