If a Recessive Allele Causes a Fatal Disease That Kills

If a recessive allele causes a fatal disease that kills the affected individual before he or she can reproduce, why doesn't that allele quickly become extinct in the population?

A) Alleles are never lost from a population.
B) The homozygous dominant individuals protect the recessive allele in their genomes.
C) The recessive allele is carried in the genome of heterozygotes, who do not suffer from the disease.
D) The homozygous recessive individuals give their alleles to other individuals before they die from the disease.