The History utility is a standard component for Lightning console apps that allows users to view their recently visited primary tabs and subtabs. Users can right-click an item in the history list and select "Copy Link Address" to get a direct URL. This URL can then be shared with other users, who can open it to navigate directly to the same record subtab, fulfilling the requirement to share links for collaboration.

A. Add the Account object to Recent Items utility.

The Recent Items utility shows a list of recently viewed records for a specific object, but the History utility is specifically designed to track and share links from the console's navigation history, including subtabs.

C. Mention the case number in a Chatter group.

While this facilitates collaboration, it does not provide a direct link to the record subtab. The other user would need to manually search for the case number, which is less efficient than sharing a direct link.

1. Salesforce Help Documentation, "Use the History Utility in a Lightning Console App": This document explicitly states, "The history utility lets your console users see their recently visited primary tabs and subtabs... To copy a link to a record, right-click the record and select Copy Link Address." This directly supports the functionality described in the correct answer.

2. Salesforce Help Documentation, "Standard Lightning Console Components": This page lists "History" as a standard utility item for console apps. It describes its function: "Lets users see their recently opened primary tabs and subtabs in a Lightning console app." This confirms it is the appropriate tool for accessing recently opened subtabs.