Which of the Following Explanations Correctly Describes a Reproductive Approach

Which of the following explanations correctly describes a reproductive approach?

A) During mitosis, DNA replication occurs twice to insure each daughter cell contains a full set of chromosomes.
B) Mitosis, followed by cytokinesis, produces daughter cells that are genetically different from the parent cell, thus insuring variation within the population.
C) In asexual reproduction, a single individual is the sole parent and passes copies of its genes to its offspring without the fusion of gametes.
D) Single-celled organisms can fuse their cells, to form new cells that are not identical to the parent cell.