<span>It sets accountability by establishing deadlines.
~Jurgen</span>
What am I supposed to do with this question, can you please reveal more of the question please so that I can maybe find a way to help you?
I believe the answer would be d.muscle cramps. Breathing in toxins seems like it could relate to the other three answers.
Answer:
Intensity
Explanation:
Each time something becomes more difficult the intensity is increasing.