Studies Show That Despite Causing a Significant Risk of Hereditary

Studies show that despite causing a significant risk of hereditary breast cancer, the BRCA1 gene has undergone strong positive selection. One hypothesis for this is that

A) BRCA1 mutations prevent viruses from using human cellular machinery to replicate.
B) mutated BRCA1 genes provided some resistance to diseases like malaria.
C) the BRCA1 gene is on the same chromosome as the gene that controls lactose tolerance.
D) mutations in tumor-suppressor genes are usually favored by natural selection.