With Respect to Genomewide Association (GWA) Studies, Which, If Any

With respect to genomewide association (GWA) studies, which, if any, of the following statements, is false?

A) The vast majority of genetic variants identified in GWA studies of complex association studies have been of weak effect, with odds ratios of 1.2 or less.
B) Even where GWA studies have identified disease susceptibility factors with odds ratios greater than 1.2, getting from disease variant to identifying a disease susceptibility locus is essentially impossible.
C) GWA studies have generally been of very limited use in predicting disease risk.
D) GWA studies have been very valuable.