An Autosomal Recessive Disorder

An autosomal recessive disorder:

A) is characterized by a 50% chance of an individual having the disease phenotype if the parents are heterozygous for the trait.
B) is defined as one in which there is a mutation in both alleles encoding for a specific enzyme/transporter.
C) affects males approximately 25% more than females because the allele is present on the X chromosome.
D) is one in which parents of diseased offspring are carriers of the condition in that they carry two mutant alleles.