Question

Natural selection theory of Darwin states that
(a) Environment doesn’t play any role in the evolution
(b) Heritable variations arise through changes in the gene complex of a species
(c) Natural selection acts on the favorable variation of a species.
(d) Characters acquired during the life of an individual are inherited by its offspring

Answer 1

Hint: Darwinism is a theory of evolution, proposed by the English naturalist Charles Robert Darwin. He thought evolution was not a sudden biologic phenomenon but a gradual one. The beneficial variation of a population works on natural selection.

Complete Answer:
A significant mechanism of evolution is natural selection. It states that species that can live and replicate under changing environmental conditions are naturally selected, while those that cannot live are discarded. Natural selection acts on the favorable variation of a species.
He based his theory on many facts, observations, and conclusions. It is
-overproduction,
- Population constancy,
- Life battle,
 - Natural selection.
Output prodigality or overproduction: Each organism has a large tendency to increase its population. Paramecium, for instance, divides three or four times a day through binary fission. At this point, the volume of the paramecia at the end of the 9000th century is 10000 times as high as that of the planet, without any control whatsoever.
Natural selection: In future generations, species with less reproductive success are not represented, but they may be in a battle for survival. This is referred to as the natural option. The survival of the fittest phenomenon was named by Herbert Spencer.
Darwinism did not clarify the process by which disparities arise. So Darwin faced the "Darwinism explains the Existence of the fittest but not the arrival of the fittest" critique.

Additional Information:
Population consistency: However, in the population of any species in nature such an unprecedented rise is not found because the offspring die in large numbers before the reproductive period. Indeed, food and other sources do not grow as much as the population.
Life struggles: because of the restricted food supplies, the population has extreme competition. The fight for life was named by Darwin.

So, the answer is, “Natural selection acts on the favorable variation of a species.”

Note: The genes that are responsible for an organism's survival are passed on to subsequent generations. Second, most features of species are inherited or transferred from parent to child, but it was unclear how traits were inherited. Second, more offspring are produced than can survive. In all species, the ability to reproduce outweighs the availability of resources to sustain their numbers. Natural selection contributes to greater population adaptation to their local environment; it is the only mechanism known for adaptive evolution.