All of the following are true of recessive alleles, EXCEPT

a. they are never transcribed and therefore never produce protein.
b. they are designated by lowercase letters.
c. the phenotype encoded by the recessive allele will only be noticeable when in the homozygous state.
d. a person heterozygous for a recessively inherited disease has one normal allele and one disease allele and is called a "carrier."