Since Leaded Gasoline Was Phased Out in the United States,one

Since leaded gasoline was phased out in the United States,one would expect to observe all of these,EXCEPT:

A) lower rates of Alzheimer's disease for those born after 1991.
B) higher rates of Alzheimer's disease in countries that continue to use leaded gasoline.
C) higher rates of Alzheimer's disease for those exposed to other lead-based products.
D) fewer neurocognitive problems among the elderly in 2010 compared to 1960.