Final answer:
An egg cell is formed by meiosis, a type of cell division that produces gametes.
Step-by-step explanation:
A. An egg cell is formed by meiosis. Meiosis is a type of cell division that results in the production of gametes, such as egg cells and sperm cells. During meiosis, a single cell divides twice to produce four cells, each with half the number of chromosomes as the original cell. This reduction in chromosome number is important for sexual reproduction as it allows for the combination of genetic material from two individuals.
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