Tetrodotoxin binds to sodium channels and blocks the passage of sodium ions. Based on this information, which symptom would most likely occur in an organism exposed to tetrodotoxin?

A.
paralysis due to lack of action potentials to signal muscle tissue
B.
blindness due to proteins in the eyes denaturing and losing functionality
C.
decreased appetite due to the production of hormones that indicate fullness
D.
increased heart rate due to increased nerve impulses to the heart muscles