Comprehensive and Detailed Explanation From Exact Extract:

Tableau Catalog provides multiple features for communicating data quality and freshness.

Data Quality Warnings (DQWs) are part of Catalog's metadata management system and are specifically designed to inform users about data issues, including when data is stale.

There are two visibility levels:

1. Standard Visibility Data Quality Warning

Appears subtly in metadata panels.

Intended for non-critical issues.

Does not guarantee the message will be seen by dashboard viewers.

2. High Visibility Data Quality Warning

Designed for urgent, critical, and highly visible alerts.

Displays a prominent warning indicator directly on connected dashboards, data sources, and workbooks.

Tableau documentation states high-visibility warnings are used when users must be alerted, such as:

Stale data

Incomplete refreshes

Data outages

Because the question emphasizes:

''important to alert dashboard viewers when data has not been refreshed''

A standard warning is not strong enough, but a High Visibility Data Quality Warning is explicitly designed for this scenario.

Evaluation of the choices:

A . Standard Visibility Data Quality Warning --- Not sufficient

It does not force dashboard users to notice the warning.

B . High Visibility Data Quality Warning --- Correct

This option is specifically meant to notify users of critical freshness issues, making it the perfect match for the requirement.

C . Certified Data Source --- Incorrect

Certification communicates trustworthiness, not freshness or alerts.

D . Lineage --- Incorrect

Lineage shows data relationships and dependencies, not refresh warnings.

Conclusion

To alert viewers about stale data in hourly-refreshed dashboards, the consultant must use a High Visibility Data Quality Warning.

Reference From Tableau Catalog Documentation

Description of Data Quality Warnings and their visibility levels.

Definition of High Visibility DQWs as critical alerts shown to dashboard viewers.

Catalog guidelines for stale data detection and communication.