Succinylcholine is structurally almost identical to acetylcholine but if combined with the enzyme that normally hydrolyzes acetylcholine, the enzyme is no longer able to hydrolyze acetylcholine. this suggests that

Answer;

-This suggests that succinylcholine must be a competitive inhibitor of acetylcholine

Explanation;

-Enzyme inhibitors are molecules that interact in some way with the enzyme to prevent it from working in the normal manner. Enzyme inhibitors include; nonspecific, irreversible, reversible - competitive and noncompetitive.

-A competitive inhibitor is any compound which closely resembles the chemical structure and molecular geometry of the substrate. In this case Succinylcholine resembles acetycholine.  The inhibitor competes for the same active site as the substrate molecule.

-Competitive inhibition occurs when a molecule mimics the substrate. Succinylcholine is neuromuscular blocking agent that is competitive inhibitor of acetylcholine at neuromuscular junction  and results in muscle paralysis.

that is wrong, its not thymus.