B

Option D involves creating a new Container Reading custom object with a master-detail relationship to Container, and implementing an archiving process that runs every hour. While this could be a valid solution, it introduces some considerations:

1. **Data Volume:** If the number of readings is expected to grow significantly over time, hourly archiving might not be sufficient to prevent data volume issues in the long run.

2. **Archiving Complexity:** Implementing an archiving process introduces complexity and maintenance overhead. Depending on the volume of data and the archiving strategy, it could impact system performance during the archiving process.

3. **Real-Time Access:** If users need real-time access to current and historical data, an archiving process might introduce delays, as it typically involves moving data to a separate storage.

Option B, creating a new Container Reading custom object without the archiving process, directly associates each reading with a container using a master-detail relationship. This ensures a straightforward and scalable solution without the complexities associated with frequent archiving....