Which of the Following Statements About Genome-Wide Association Studies (GWAS)

Which of the following statements about genome-wide association studies (GWAS) is FALSE?

A) GWAS use SNPs to compare populations of people with disease and people without disease to look for SNPs more likely to be present in those with disease.
B) GWAS can be used even if more than one gene can cause the disease of interest.
C) Sometimes GWAS will identify SNPs that are associated with a disease, but these SNPs do not affect the gene product of the gene that causes the disease.
D) Studies using GWAS only examine SNPs that occur very rarely (<0.001%) in the population, as those SNPs are most likely to cause disease.