A. People
B. Process
C. Security
D. Things

Solution

C. Security

Explanation

<p>While security is extremely important in IoT systems, it is generally considered a supporting or enabling feature, not one of the core/main elements of IoT.</p><p>The main elements of IoT are often referred to as:</p><ul><li>People – Users or stakeholders interacting with the system.</li><li>Process – How the data is analyzed and used to make decisions.</li><li>Things – Devices or sensors that collect and send data.</li></ul>