The Public Group and Sharing Rule approach grants access to specified users and, by default, extends access to their managers in the Role Hierarchy. Here’s how the settings interact:

Public Group: The group includes a specific set of sales engineers.

Sharing Rule: It grants access to opportunities for the Public Group. This rule respects the existing Role Hierarchy.

Role Hierarchy: In Salesforce, managers in the hierarchy automatically gain access to records their subordinates can access, ensuring seamless visibility for leadership.

Option A (Correct): Managers of sales engineers in the Role Hierarchy will gain access because sharing rules honor the Role Hierarchy.

Option B: Subordinates of managers will not gain access because sharing rules do not propagate access downward in the hierarchy.

Option C: Other sales engineers outside the specified Public Group will not gain access unless explicitly included in the sharing rule.