A cross is made between an Hfr strain that is StrSa+b+d+ in genotype and an F- strain that is StrRa-b-d- in genotype.Interrupted-mating studies show that b+ enters the recipient strain last,and that the Str locus is very far away from b+,so it never enters the recipient strain.The b+ recombinants are then tested for the presence of the a+ and d+ alleles.The following data were obtained: a+a−a+a−b+b+b+b+d+d+d−d−32621458400 a)What is the gene order?
A)a d b Str B)b a d Str C)b d a Str D)d a b Str E)d b a Str