Variations are observed in the offspring of sexually reproducing organisms.

Concept: The above given statement is true.

1. Male and female gametes combine during sexual reproduction, resulting in the blending of parent characteristics and the variance seen in the progeny of sexually reproducing animals. 
2. The diversity of personalities in the progeny is encouraged by sexual reproduction. 
3. It causes the gamete to have new gene combinations, and this rearranging broadens the genetic diversity of the organism. It is crucial to the development of new species. 
4. The process of fusing two different people's DNA during reproduction occurs during the sexual mode of reproduction.

Hence, option A is the correct answer.