The correct answer is: The tetraploid (4n) flower produces 2n gametes and may then be able to self-pollinate to produce fertile 4n offspring.
Gametes are produced via meiosis, which is reduction cell division, meaning that cell from diploid (2n) becomes with haploid (n) number of chromosomes. In the example above, 4n flower will produce 2n gametes. Ovary of the flower produces ovule-the female gamete which is ready for fertilization. The anther produces pollen that lands on a mature stigma of a flower and grows a pollen tube down into the flower. Pollen then produces male gametes-sperm by mitosis and releases them for fertilization.