What is the minimum depth for chest compressions in adult CPR?

In adult CPR, the minimum depth for chest compressions is set at 2 inches (5 cm). This depth is crucial because it ensures that adequate compression is applied to the chest, allowing for effective blood flow to the heart and brain during cardiac arrest.

When compressions are performed at this depth, it creates sufficient pressure to facilitate the return of blood to the heart when the chest is released. Compressions that are too shallow might not generate the necessary pressure to maintain circulation, which can compromise the victim's chances of survival. By adhering to the guideline of at least 2 inches, rescuers can significantly enhance the likelihood of maintaining perfusion until advanced medical help arrives.

The other options suggest depths that either do not meet the minimum requirement or exceed what has been established as necessary for effective CPR in adults. Hence, adhering to the recommended minimum ensures a balance between effectiveness and safety during resuscitation efforts.