The correct option is C one dominant allele and one recessive allele
Each gene has alternative forms, called alleles. The allele which is expressed is called the dominant allele. The other one is the recessive allele which in the presence of the dominant allele does not express. Heterozygous individuals have one dominant and one recessive allele whereas homozygous individuals would have two alleles of the same type, i.e., either both dominant or both recessive. A trait is the specific characteristic of an organism which is determined by genes. The recessive trait is expressed only in the homozygous condition, that is in the absence of the dominant trait.