The correct answer is B) respiration is weak or has stopped. In the case of cardiac arrest resulting from electric shock, the primary symptom is the cessation or severe weakening of respiration, as the electric shock can disrupt the normal electrical impulses that control the heart and respiratory system. This leads to the heart stopping and the victim's breathing becoming weak or stopping altogether. The other options, while potentially relevant in other medical emergencies, are not the primary symptoms observed in a victim of cardiac arrest due to electric shock. A weak pulse may be present, but the lack of respiration is the more critical and defining symptom in this situation.