10 years ago, a father’s age was \(3\frac{1}{2}\) times that of his son, and 10 years from now, the father’s age will be \(2\frac{1}{4}\) times that of the son. What will be the sum of the ages of the father and the son at present?

• A. 115 years
• B. 100 years
• C. 110 years
• D. 120 years