Final Answer:
Hemophilia is a sex-linked disease. Option C is the answer.
Step-by-step explanation:
Hemophilia is a genetic disorder characterized by impaired blood clotting, leading to prolonged bleeding even from minor injuries. The genes associated with hemophilia are located on the X chromosome, making it a sex-linked disease. Since males have one X and one Y chromosome, a mutation in the single X chromosome they inherit from their mothers results in the expression of hemophilia. Females, with two X chromosomes, are carriers and may pass the mutated gene to their offspring.
Tay-Sachs disease, Huntington's disease, and cystic fibrosis are not sex-linked diseases. Tay-Sachs and Huntington's are autosomal recessive and autosomal dominant disorders, respectively, while cystic fibrosis is an autosomal recessive genetic condition.
Option C is the answer.