How is an allele described?

a.

short segment of DNA

b.

form of a gene

c.

part of a chromosome

d.

one haploid cell

b. form of a gene

Explanation:

An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosome. Genotypes are described as homozygous if there are two identical alleles at a particular locus and as heterozygous if the two alleles differ.