def enable_explicit_action(options, explicit_action):
    """
    Explicitly enable an action and disable other implicit actions.

    :param options: A dictionary of options.
    :param explicit_action: The action to enable (one of the strings
                            'backup_enabled', 'snapshot_enabled',
                            'rotate_enabled').
    """
    options[explicit_action] = True
    for implicit_action in ('backup_enabled', 'snapshot_enabled',
        'rotate_enabled'):
        if implicit_action != explicit_action:
            options.setdefault(implicit_action, False)
