An Older Client with Mild Alzheimer's Disease Abruptly Stops Taking

An older client with mild Alzheimer's disease abruptly stops taking the prescribed medication donepezil (Aricept) . When assessing the patient for withdrawal symptoms of the the sudden discontinuation of the medication, on which area should the nurse focus?

A) The client's reflexes
B) The client's rest and sleep pattern
C) The client's cognitive function
D) The client's cardiovascular function