Which statement about the depth of chest compressions is correct?

• A. 2 cm
• B. 5 cm
• C. 7.5 cm
• D. 10 cm

Answer: (B)

The key idea here is the recommended depth of chest compressions during adult CPR. For adults, aim for a depth of about 5 cm (roughly 2 inches). This depth is deep enough to generate adequate intrathoracic pressure and ensure effective blood flow to vital organs, including the heart and brain.

If the compressions are too shallow, like 2 cm, they won’t create enough pressure to circulate blood effectively. If they’re much deeper, such as 7.5 cm or 10 cm, they increase the risk of injury without providing extra benefit and can cause harm. Therefore, 5 cm is the best answer because it aligns with the guideline minimum that balances efficacy and safety.