When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is

The correct option is C Tetraploidy

• When the male plant is tetraploid the gamete formed after meiotic division will be will be diploid.
• The female plant is diploid as a result, the gamete formed after the meiotic division will be haploid.
• The endosperm cell is formed by the fusion of two polar nuclei and one male gamete.
• The two polar nuclei means (n+n) =2n and one male gamete = 2n, which fuses to form an endosperm cell = 4n or tetraploid.
• So, the correct answer is 'Tetraploidy'.