Final answer:
Succinylcholine is the depolarizing neuromuscular blocker most likely to be used for rapid sequence intubation due to its rapid onset and short duration of action.
Step-by-step explanation:
The depolarizing neuromuscular blocker most likely to be used in rapid sequence intubation, which is a procedure performed when there's a significant risk of reflux and aspiration of stomach contents, is (B) Succinylcholine. This drug is chosen due to its quick onset and short duration of action, making it suitable for this emergency procedure. The other options listed do not perform the same rapid depolarizing function as succinylcholine; for example, baclofen is a muscle relaxant and GABA derivative, and neostigmine, homatropine, and pralidoxime have different mechanisms of action that are not relevant for rapid sequence intubation.