<span>The sex cells, more scientifically known as the ova and spermatozoa, are composed of 23 of the usually 46 human chromosomes. They have half the usual number because they of course combine to form a new, genetically distinct, cell, termed the zygote. The correct term for this type of cell, one with half of the complete genome, is GAMETE. Therefore the answer is option (a).</span>
