What device is used to deliver electrical impulses to regulate the heartbeat?

The device used to deliver electrical impulses to regulate the heartbeat is a pacemaker. This small electronic device is implanted in the chest or abdomen and helps to maintain an adequate heart rate when the heart's natural pacemaker fails to function properly or when there are other heart rhythm issues. It generates electrical impulses that prompt the heart to beat at a normal rate, ensuring that blood is effectively circulated throughout the body.

In contrast, the other options do not relate to heart function. A dropper is typically used for dispensing liquids, a repellent is designed to keep pests away, and tweezers are a tool for grasping small objects. Each of these serves quite different purposes in various contexts, which highlights the specific and crucial role of the pacemaker in cardiac health.