Both Pierre's Biological Parents Had Bipolar Disorder

Both Pierre's biological parents had bipolar disorder.When he was four months old, he was adopted by a family that has no history of bipolar disorder.In these circumstances, Pierre has:

A) an increased risk for developing bipolar disorder, even if he has no contact with his biological parents
B) an increased risk for developing bipolar disorder, but only if he maintains contact with his biological parents
C) the same risk for developing bipolar disorder as the rest of his adopted family's children
D) no increase in his risk for developing bipolar disorder, but an increase in his risk for other psychological disorders