What is the primary reason meiosis occurs in reproductive cells?

Meiosis is a specialized type of cell division that occurs in reproductive cells and is crucial for sexual reproduction. The primary function of meiosis is to reduce the chromosome number by half, transitioning from diploid (two sets of chromosomes) to haploid (one set of chromosomes) in gametes (sperm and eggs). This is key because when two gametes fuse during fertilization, the diploid state is restored, maintaining the species' chromosome number across generations.

Creating haploid cells is critical for genetic diversity and adaptation, as it allows for the combination of genetic material from two parents, resulting in offspring that are genetically distinct from both parents. This mixing of genetic traits is essential for evolution and can contribute to the survival of a species through variability.

The other options do not relate to meiosis's primary function. Increasing cell size is not a characteristic of meiosis; rather, the focus is on division and reduction of chromosome number. Producing energy and repairing damaged cells are functions associated with cellular metabolism and mitosis, respectively, not meiosis. Thus, the successful generation of haploid gametes is the cornerstone of meiosis in reproductive cells.