This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
Morphine can administered by all of the following routes except: 
Select and explain. 
A. Intramuscular, B. Transdermal, C. Epidural, D. Subarachnoid
D: Subarachnoid
Answer: D: Subarachnoid 
Explanation: Ref: KDT 6/e p458 *Respiratory depression occurs due to depression of respiratory centre by morphine travelling through the subarachnoid space Routes of administration of morphine are: -Oral -Rectal -Intramuscular -Intravenous -Transdermal -Subcutaneous