Prodigality of reproduction in Darwinism refers to:

Who stated that variations which are heritable and which make resource utilization better for few will enable only those to reproduce and leave more progeny?

The theory of natural selection is based on which of the following?

Assertion : Natural selection is the outcome of difference in survival and reproduction among individuals that show variation in one or more traits.
Reason : Adaptive forms of a given trait tend to become more common; less adaptive ones become less common or disappear.

$A$: $A$ single large mutation called saltation can produce new species.
$R$: Mutations are directional.

Darwin,in his 'Natural Selection Theory',did not believe in any role of which one of the following in organic evolution?