In corn R is a gene for red aleurone;its recessive allele r determines colorless aleurone.A cross is made between a diploid r/r female and a trisomic R/r/r male.If pollen grains with extra chromosomes are inviable,the ratio of red to colorless kernels expected in the progeny would be:
A)1 red : 5 colorless. B)1 red : 2 colorless. C)1 red : 1 colorless. D)2 red : 1 colorless. E)5 red : 1 colorless.