Statement (S ) `:` The concept of survival of the fittest is central to natural selection.
Reason (R ) `:` Individuals who posses advantageous characters to adapt to the environment have better potential for survival.

The correct statements about the survival of the fittest are I. the term survival of the fittest was coined by Herbert Spencer. II. Natural selection tends to favour fittest organisms III. Fittest means more healthy, but sterile. IV survival means less healthy, but sterile.

Which is not a correct statements ? (A) Variations are the raw materials for evolution (B) Variations provide genetic material for natural selection (C) It helps the individual to adapt to changing environment (D) Variations allow breeders to improve the crop field

Assertion (A): Variations help the individuals to adapt themselves to the changing environment. Reason (R ) : It provides the genetic material for natural selection.

Assertion (A): Natural selection is the phenomenon by which the nature selects those species which possess survival advantage over the other species. Reason (R): According to theory of natural selection, there is struggle of existence within the species of a population for the environmental resources and their struggle leads to survival of certain organisms and elimination of the less competent species. a) Both A and R are true and R is the correct explanation of A. b) Both A and R are true but R is NOT the correct explanation of A. c) A is true but R is false. d) A is false and R is true.

Statement (S). Arthropoda are the most successful of all known animal groups Reason (R). Arthropoda exhibits the greatest adaptive radiations and have adapted to diverse habitats.

Statement (S). Arthropoda are the most successful of all known animal groups Reason (R). Arthropoda exhibits the greatest adaptive radiations and have adapted to diverse habitats.

Statement (S). Arthropoda are the most successful of all known animal groups Reason (R). Arthropoda exhibits the greatest adaptive radiations and have adapted to diverse habitats.

Statement (s ) : Populations of a species inhabiting different geographical areas are in a continuous process of adaptation to their surrounding environments and this leads to the evolution of species. Reason (R ) : Geographical barriers obstruct interbreeding of populations of a species leading to reproductive isolation and evolution of new species.

Which of the following statements about natural selection are correct? (i) Tends to increase the characters that enhance survival and reprocution (ii) Inviduals with better adaptive ability leave more progeny (iii) Was considered as mechanism of evolution by Darwin