Based on Known Facts About the Genetic Influences on Alzheimer's

Based on known facts about the genetic influences on Alzheimer's disease, it appears that there may be several genetic causes, which may influence the course and age of onset for the disorder.For example, genetic research has found an association between chromosome 14 and chromosome 19 and specific types of Alzheimer's disease.What are these types, respectively?

A) late onset and early onset
B) early onset and late onset
C) irreversible and reversible
D) reversible and irreversible