Explain the example of insect resistance to pesticides as an instance of natural selection.

In which of the following organisms is the rate of appearance of new forms the highest?

Given below are two statements regarding evolution.
$Statement-I$: Isolation is the separation of a population of a particular species into smaller units, which prevents interbreeding between them.
$Statement-II$: Due to isolating mechanisms, divergence and speciation do not occur.
In the light of the above statements, choose the most appropriate answer from the options given below.

Darwin judged the fitness of an individual by

In natural selection, more individuals acquire value other than the mean character value, which indicates . . . . . . .

Natural selection is based on which of the following?