Answer:
The correct option is C.
repaying an oxygen debt.
Explanation:
This is because while running, humans breath shallowly which could not provide the oxygen requirement for the respiratory system and fit in for blood need.
After running, you tend to breathe heavily because your muscle work very hard , the body use more oxygen and produced more carbondioxide, therefore the lungs and respiratory system must try to provide more oxygen to the blood. sympathetic nerves stimulate respiratory muscles
so as to increase the rate at which we breathe.
Carbon. This is easy to even guess, from CARBOhydrates for those who don't know, and fats are generally just liked up carbohydrates in certain structures.
Complete a Punnett Square to see the possible offspring.
. R I r
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r I Rr I rr I
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r I Rr I rr I
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Excuse the horrible square, but as you can see, the possible genotypes will be Rr and rr.
The answer that best fits the blank is "RELIABLE, BUT NOT A VALID". Sir Francis Galton is a known anthropologist and eugenicist, and for him, skull size in relation to intelligence might be reliable, but this do not have any evidence to be considered valid.