Answer:
Option B , heterozygous
Step-by-step explanation:
A heterozygous allele pair (gene) consists of two different alleles for the same trait (such as height, color, texture etc.)
For example -
Let "R" represents the allele for red color of flower
and "r" represent the allele for white color of flower
Then Allele pair "RR" and "rr" are called as homologous allele pair having same kind of alleles
While the allele pair "Rr" represents the heterozygous allele pair.
Hence, option B is correct