Where any person who has held the office of Governor General has immediately preceding his or her appointment to that office been in service in the permanent civil service and is not in receipt of a pension in respect of that service, he or she may opt—
(a) to receive a pension under section 7, if he or she is so entitled; or
(b) to treat his or her service in the office of Governor General as service in the permanent civil service and receive a pension, or a pension and reduced gratuity or any applicable gratuity under the Pensions Act if the length of his or her joint service in the office of Governor General and his or her service in the permanent civil service qualifies him or her for a pension or gratuity under that Act, and he or she shall be granted a pension under section 7 or a pension or reduced pension and gratuity or other gratuity under the Pensions Act as he or she so opts.