At the End of World War II, American Soldiers Both

At the end of World War II, American soldiers both black and white, who were stationed in Germany, fathered thousands of children with German women. Research on random samples of these children found

A) incredible difference between child with regards to IQ, along lines of nationality.
B) having a white father conferred no measurable IQ advantage at all
C) a difference the children, related to the IQ of their grandparents, but not their parents.
D) racial differences favouring black children, which the researchers concluded was due to a more engaging environment.