The Answer is correct... it is B.
The comment from "Nora" is incorrect.

🧠 Why This Happens:
When converting a field from Date → Date/Time in Salesforce:

The date portion of each record remains unchanged.

Since Date fields don’t store time values, Salesforce defaults to 12:00 PM (noon) as the time.

This is true for every existing record unless a time was previously captured in another field.

In other words, your Shipment_Date__c might go from: 2025-07-11 → 2025-07-11 12:00 PM

⚠️ Key Considerations:
It’s not true time data — dispatchers shouldn’t rely on the 12:00 timestamp for historical accuracy.

Reports, flows, or automations using this timestamp should be adjusted to avoid false assumptions.

If dispatchers need actual sent-out timestamps, you’ll need to pull that from logs, external data sources, or implement proper time capture moving forward.

Would you like help creating a rule or automation to ensure dispatchers always input a precise timestamp for future shipments? I can help set it up for better data fidelity 🚚📅🕒...

It's D definitely. Tried and tested