Which among the following sequences was proposed by Darwin for organic evolution?

The correct option is A Overproduction $\to$ Struggle for existence $\to$ Variation $\to$ Survival of the fittest

According to Darwin's theory, overproduction increases the demand for food and space within that location, thereby creating a struggle for existence among the organisms. Those organisms that exhibit a particular variation to fight against the environmental challenges survive and are considered to be the fittest in the population.