oxygen

Premise1:- One of the limiting factors is the amount of oxygen absorbed by muscles from bloodstream
Entrepreneurs have started selling Water X, which has more oxygen than does normal water
Conclusion:- Water X is useless
Reason:- Amount of oxygen in the blood of person who is exercising is already more than the muscle cells can absorb
This is supporting the conclusion that Selling Water X is useless. We need to find an answer choice that does the same

a)Does not support the argument( this choice is only about world class athletes)
b)Accepting this as true will not mean selling Water X would be useless
c)If lungs are the only means through which oxygen can be absorbed then consumption of water X would indeed be useless
d)No one is denying this..argument itself states that lack of oxygen is one of the limiting factors...
e)If the water lost can be replaced with ordinary tap water, so be it. There is no discussion of oxygen, limiting factors....hence this is not relevant to the argument

I'll go with C

Cheers,
Unplugged