A psychologist wants to make a case that observed differences in IQ among racial groups are not due ...

A psychologist wants to make a case that observed differences in IQ among racial groups are not due to inherited intelligence differences.
 
  If she were to draw on the evidence provided by the research of Brooks-Gunn, Klebanov, and Duncan, which argument would she make? a) After controlling for poverty and its cofactors, the observed racial differences disappear.
   b) Individual heritability of IQ does not mean that racial group IQ differences are based in genetics.
   c) Race is a social construct without biological meaning.
   d) Observed differences in IQ among racial groups have declined since 1970.