An individual having different alleles of a gene is
A.Heterozygous – An individual having different alleles of a gene is called Heterozygous
B.Homozygous – An individual having similar alleles of a gene is called Homozygous.
C.Diploid – An individual with a two sets of chromosomes is called Diploid.
D.Mosaic – an individual, composed of cells of two genetically different types.
So, the correct option is ‘Heterozygous’.