Which secretion is most likely lacking in the brain of an Alzheimer's patient?

Which secretion is most likely lacking in the brain of an Alzheimer's patient?
A. ATP
B. Acetylcholine
C. Transfer RNA
D. Cholinesterase

In order to develop a procedure that would restore hearing in individuals with hearing loss caused by damage to hair cells, similar research must be done on the hair cells found in the
A. Saccule
B. Cochlea
C. Auditory Canal
D. Semi-circular Canals

The pituartary hormone ACTH regulates the production of aldosterone by the cortex of the adrenal glands. A severe drop in ACTH levels would likely result in
A. decreased sodium ion retention and increased water loss because aldosterone levels would rise
B. decreased sodium ion retention and increased water loss because aldosterone levels would drop
C.increased sodium ion retention and incerased water retention because aldosterone levels would rise
D.increased sodium ion retention and incerased water retention because aldosterone levels would drop

Olfactory receptors are categorized as
A. mechanical receptors that are attached to the dendrites of neurons
B. mechanical receptors that are attached to the axons of neurons
C. chemoreceptors that form a synapse with the dendrites of neurons
D. chemoreceptors that forms a synapse with the axons of nuerons