Humans Suffer from Dementia (Similar to Alzheimer's Disease) If They

Humans suffer from dementia (similar to Alzheimer's disease) if they eat flour made from cycad seeds because:

A) The seeds have high levels of manganese that is a cause of dementia.
B) The seeds contain hallucinogenic drugs similar to LSD that causes dementia.
C) The seeds have enzymes that break down brain tissue causing dementia.
D) The seeds contain the amino acid BMAA that causes dementia.
E) The seeds have enzymes that inhibit absorption of nutrients that are essential for the transmission of nervous impulses in brain cells.