Final answer:
President Ford cites that Nixon has suffered enough as the major reason for issuing the pardon.
Step-by-step explanation:
President Ford cites the major reason for issuing the pardon to Nixon as option C, which is that Nixon has suffered enough. Ford believed that the prolonged investigation and public scrutiny had taken a heavy toll on Nixon's health and personal life. Furthermore, he wanted to help heal the nation's divisions and move forward, and believed that a trial or any legal actions against Nixon would only further polarize the country.
Learn more about President Ford's pardon of Nixon