What does Dr. Luiders study tell us about the pregnancy zone protein？A．It never increases

What does Dr. Luiders study tell us about the pregnancy zone protein？

A．It never increases before the appearance of Alzheimer"s symptoms.

B．Levels of it remain stable for men"s lifetime.

C．Women developing Alzheimer"s usually have lower levels of it.

D．The brain plaques connected with Alzheimer"s produce it.

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