In a wild-type fungus,protein E (encoded by the haplosufficient gene "E")normally homodimerizes,and the E-E dimer catalyzes a biochemical reaction necessary for the production of a dark pigment.E^D represents a mutant,dominant,negative allele of gene E.What is the predicted phenotype of a fungus cell of genotype E⁺/E^D,and why?

A)mutant (no pigment production),as E is haplosufficient
B)mutant (no pigment production),as no E-E dimers will form in the heterozygous
C)mutant (no pigment production),as the mutant allele E^D is dominant
D)wild type (normal production of the dark pigment),as E^D is a negative allele
E)wild type (normal production of the dark pigment),as E is haplosufficient