I would say c) increase crash energy because since they are speeding they are more likely at risk of crashing into things or even people.
The least likely explanation for this would be that they're training at different intervals, or one is training harder than the other.
The most likely reason is that the way the other person's genetics are most people cant gain muscle as well as others because of disease or their body structure.
Hope this helped!
<u><em>Digestive</em></u> is a system prepares food for absorption into the bloodstream.So the answer for your question is Digestive.
Hope this helps:)