Comprehensive and Detailed Explanation (Based on NREMT standards):

Electrical injuries commonly disrupt the heart’s electrical conduction system. NREMT teaching emphasizes that cardiac dysrhythmias are the leading cause of unresponsiveness following electrical exposure, even when external burns appear minor.

Option A is correct because electrical current can induce lethal dysrhythmias such as ventricular fibrillation or asystole, resulting in sudden loss of consciousness.

Option B is incorrect because internal bleeding is not a primary consequence of electrical injury.

Option C may occur but does not typically cause immediate unresponsiveness.

Option D is less likely than cardiac involvement and is not the most common cause.

NREMT stresses continuous cardiac monitoring and rapid transport for all electrical injury patients due to the high risk of sudden cardiac arrest.