In males, X-linked characters are

The correct option is D hemizygous
If both alleles of a diploid organism are the same, the organism is homozygous at that locus. If they are different, the organism is heterozygous at that locus. If one allele is missing, it is hemizygous. Sex linked characters are hemizygous (only one copy of the gene is present) in males, since males have only one X chromosome.