A73-year-old woman comes to the office for evaluation of new onset of tremors. she is not taking any medications, herbs, or supplements. she has no chronic medical conditions. she does not smoke or drink alcohol. she walks into the examination room with slow, shuffling steps. she has decreased facial mobility with a blunt expression without any changes in hair distribution on her face. based on this description, what is the most likely reason for the client's symptoms? a. nephrotic syndromeb. myxedemac. cushing's syndromed. parkinson's disease