The statements that apply are;
Males don’t have a second X chromosome to mask the effects of the first one.
While females would need two of these alleles to express the recessive phenotype, males only need one
Males have XY homologous sex chromosomes while females have XX. The Y chromosomes have very few genes compared to the X sex chromosome. Therefore the male is usually hemizygous for most sex-linked genes. This makes them vulnerable to sex-linked disorders if the gene they inherit from the mother is recessive