All but one factor contributes to natural selection. that factor is

Phenotype

Explanation:

Natural selection is a process by which heritable traits conferring survival and reproductive advantage to individuals, or related individuals, tend to be passed on to succeeding generations and become MORE FREQUENT in a population, whereas other LESS favourable traits tend to become ELIMINATED

.

The factors contributing to natural selection are four. They are reproduction, variation, Heredity, survival fitness level (based on traits).

However, the phenotype (observable characteristic of an organism) DO NOT contribute to natural selection. A plant specie is not selected by nature JUST because it is TALLER, it must also be that that trait of tallness aids its survival or else, it will be ELIMINATED.

So, the all but one factor is Phenotype.

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.  

well for one plants are always the producer, so a is the answer. a wolf is more of the consumer(predator) and the deer is the prey so i know those two are out of the question. also mushrooms are fungi/fungus so a is the producer.