I think that it is either D or maybe C
The answer is "I" , whenever it mentions doing something you use "I" when speaking about yourself.
The answer is A the pacing and setting of the book to give a feel for the rhythm
-the beauty of athletics is that in truth nothing is impossible, like all those records that were once deemed impossible to
-to become a world class athlete is beyond dedication and practice, other factors like financial status, genetic advantages, environment, country of origin and (other points you might want to add), are all beyond personal control.