Suppose an Individual Is Heterozygous for a Pair of Alleles

Multiple Choice

Suppose an individual is heterozygous for a pair of alleles (e.g., A/a) .Under what conditions would a crossover in a somatic cell of this individual lead to a clone of cells homozygous for a? (Pick the most precise answer.)

A) The crossover would have to occur between the A locus and the centromere and involve two homologous (non-sister) chromatids.
B) The crossover would have to occur between the A locus and the end of the chromosome and involve two homologous (non-sister) chromatids.
C) The crossover would have to occur on the same chromosome arm as the A locus and involve two homologous (non-sister) chromatids.
D) The crossover would have to occur on the same chromosome as the A locus and involve two homologous (non-sister) chromatids.
E) The crossover would have to occur between the A locus and the centromere and involve two sister chromatids (not homologous) chromatids.