This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
The drug that produces neuromuscular blockade by persistent depolarization is: 
Select and explain. 
A. D-tubocurarine., B. Gallamine., C. Pancuronium., D. Decamethonium.
D: Decamethonium.
Answer: D: Decamethonium. 
Explanation: Decamethonium is a peripherally acting skeletal muscle relaxant. It produces an immediate and rapid depolarization of the motor end plate. D-tubocurarine, pancuronium and gallamine are competitive antagonists of acetylcholine at the motor end plate and produce skeletal muscle relaxation.