Which of the following security measures is MOST important for protecting Internet of Things (IoT)...

Changing default passwords is a critical security measure for IoT devices. Many IoT devices come with default credentials that are widely known and easily exploitable by attackers. Ensuring that these default passwords are changed to strong, unique passwords significantly reduces the risk of unauthorized access. While logging, monitoring, firmware compliance, and network diagram reviews are important security practices, they are secondary to the fundamental step of securing device access through strong authentication.