Which of the following data update settings for a single score visualization shows the timestamp of when the score was last updated?

The option that accurately represents the data update setting for a single score visualization showing the timestamp of when the score was last updated is the one that specifies to "Show score update time." This setting is specifically designed to display the last updated timestamp alongside the score, providing users with clear visibility into how current the data is. This can be particularly important in analytics, where the recency of data can significantly impact decision-making processes.

In contrast, real-time updates refer to the continuous refresh of data as new information becomes available, but do not explicitly show when the last update occurred. Background refresh intervals focus on how frequently the data is refreshed in the background without affecting the dashboard's performance but do not provide a timestamp for users to reference. Following filters is about applying specific filters to the data visualization, which does not pertain directly to displaying an update timestamp. Hence, the clarity and utility of showing a timestamp for the last update make the correct choice the most suitable option in this context.