Geneticist have determined that the majority of individuals in an isolate island population have blood type b. type a blood is found to be more common in the mainland populations from which the island was settled. how would a geneticist explain the dominance of blood tpe b in the island population. a- random mutations have occurred in the island population. b- genetic drift has reduced the frequency of type a individuals. c- natural selection has only occurred in the mainland population. d- environmental conditions on the island are less favorable for type b individuals.