What do rules in Outlook mainly accomplish?

The primary function of rules in Outlook is to automate tasks that would otherwise require manual effort when managing incoming messages. By creating a rule, users can set specific criteria that determine how messages are handled as they arrive in the inbox. This automation drastically reduces the need for manual filing, as it enables emails to be sorted, moved to designated folders, or flagged for follow-up automatically upon arrival based on the defined parameters.

Using rules allows for a more efficient workflow and enhances productivity, as it minimizes the time spent on email management tasks. While organizing emails and even deleting unwanted messages can be part of what rules accomplish, the central premise is the reduction of manual actions, making option C the most encompassing and accurate reflection of what rules do in Outlook.