Universal Containers has a custom Agent action calling a flow to retrieve the real-time status...

When a flow is invoked via a custom Agent action, its data access depends on the flow’s runtime configuration, not system mode by default. Salesforce flows can be configured to respect the running user’s permissions and sharing settings:

If the flow is set to "Run as the User Who Launched the Flow" (enabled in Flow Settings), it adheres to the user’s permissions, field-level security (FLS), and sharing rules.

Option C is incorrect because flows do not always run in system mode unless explicitly configured to do so.

Option A is misleading because "with sharing" is an Apex concept, not a flow setting. Flows use runtime settings like FLS and sharing enforcement.