Sushant said to him, “I have been helping your son for years.”

• A. Sushant told him that he has helped his son for years.
• B. Sushant told him that he have been helping his son for years.
• C. Sushant told him that he had been helping his son for years.
• D. Sushant told him that he has been helping his son for years.

• Sushant told him that he had been helping his son for years.

Please select one of the options to reveal the correct answer.