Which of the following was $NOT$ considered a part of Darwin's theory of natural selection in organic evolution?

Select the incorrect statements:
$I.$ Natural selection is essential for evolution.
$II.$ Natural selection does not include variations.
$III.$ The concept of natural selection was given by Hugo de Vries.
$IV.$ Mutation is a sudden inheritable change.
$V.$ The synthetic theory is also called the Neo-Darwinism theory of evolution.

Find the mismatch from the following pairs.

Sewall Wright effect is . . . . . . .

What is hybrid breakdown a failure of?

The chances of a mutant gene spreading in a population increase when it is .......