Why the answer is A?

Becuase A makes sence  

Explanation:

Option A

Explanation:

The heterozygous allele can be defined as the condition in which the organism has two different alleles of the gene.

It is represented as Rr, means a capital letter and a small letter. This hows that the organism has one dominant gene and one recessive gene in it.

This dominant and recessive condition decides the genotype and phenotype of organism.