Which ISA/IEC 62443 part covers technical security requirements used by product suppliers, integration service providers,...

ISA/IEC 62443-3-3 defines system-level security requirements applicable across roles.

Step 1: System focus

Part 3-3 specifies technical security requirements for IACS systems, independent of who implements them.

Step 2: Multi-role applicability

These requirements are used by:

Product suppliers (design alignment)

System integrators (implementation)

Asset owners (operation and verification)

Step 3: Distinction from other parts

2-1 focuses on management systems

2-4 focuses on service providers

4-2 focuses on component-level requirements

Thus, Option C is correct.