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.

ans.

gregor john mendel is known for study of inheritance in pea plants. he used garden pea plant for his study, having alternative traits for various characters. he performed cross-breeding in pea plants to check how characters are transmitted between parents to offspring, such as cross between pure tall and pure dwarf plant. mendel studied the inheritance patterns in pea plants for various generations.

thus, the correct answer includes options and f).