ADE enforces OS requirements. The Apple Platform Deployment Guide states, "When a device attempts ADE and doesn't meet the minimum OS version specified in the MDM profile, it will download and install the required update during Setup Assistant, then resume the enrollment process automatically." Options B, C, and D don't align with this process.
Reference:
Apple Platform Deployment Guide, "Automated Device Enrollment" section.
iOS Deployment Reference, "ADE Workflow" section.