In humans,an X-linked disorder called coloboma iridia (a fissure in the iris)is a recessive trait.A normal couple has an afflicted daughter.What would be the most plausible scenario for this situation?  

A) The mother carries two recessive alleles.
B) The father carries one recessive allele, and the mother carries one recessive allele.
C) The female is not the biological mother, but the male is the biological father.
D) The male is not the biological father, but the female is the biological mother.
E) Both parents are heterozygous for the trait.