What is the best description of an organism that is fit for natural selection?
the organism is physically stronger than competing organisms.
the organism is physically stronger than organisms of a different species.
the organism is better able to survive and pass on traits to offspring than competing organisms.
the organism is a member of a population in which every member survives without competing.

The answer is C: The organism is better able to survive and pass on traits to offspring than competing organisms.

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.