Answer:
The correct answer is "immediate recognition of cardiac arrest and activation of the emergency response system".
Step-by-step explanation:
The first link in the Chain of Survival for an adult (IHCA) involves performing actions of surveillance, prevention, and treatment of prearrest conditions. Once the first link has finished, the second link in the IHCA is to perform immediate recognition of cardiac arrest and activation of the emergency response system. This is a critical step to achieve a successful resuscitation maneuver, which saves lives of people that are suffering a cardiac condition.