. Which statement best describes the relationship between an allele and a gene?
A. An allele is a variation of a gene that can be expressed as a phenotype.
B. An allele is the part of a gene that attaches to messenger RNA molecules.
C. An allele is a segment of a DNA molecule that controls replication of a gene.
D. An allele is the primary protein made by a gene found in a developing embryo
(I did to know why the wrong answers are wrong.)