An organism is born with a genetic variation not present in any of its ancestors. This variation is most likely the result of A. circulation of blood
B. competition among individuals
C. respiration
D. a mutation in its DNA

D

Explanation:

This is because circulation in blood, respiration and competition have no relation to changing the DNA of an organism

complete the square on the right side of the equation;

-5(x + 0)^2 + 15

answer: d. y = -x^2 + 15

as the gila monster consumes the eggs or young of the desert cottontail and gambel's quail, thus its main food supply is only accessible for a restricted time duration every year. however, for this, the gila monsters exhibit three adaptations, which elevate their survival rate in the desert condition.  

first, is that they possess huge bodies, and can consume greater concentrations of food during a small period. secondly, they require to feed infrequently as they can accumulate fat in their tails. ultimately, their rate of metabolism is very low, so that they can burn their reservoirs of fat gradually.