Deploy a traditional antivirus solution across all devices, assuming it will suffice for OT and ICS environments due to its widespread use in IT environments.

Implement a dedicated security solution like Microsoft Defender for IoT, which is specifically designed for OT and ICS environments, offering advanced threat detection and compliance with industry standards.

Rely on the built-in security features of OT and ICS devices, considering them adequate for protection against modern cyber threats.

Focus exclusively on enhancing the network perimeter security, under the assumption that internal threats are negligible.