Which of the following differential equations has the solution y=3x2?

• A. \(\frac{d^2 y}{dx^2}\)-6x=0
• B. \(\frac{dy}{dx}\)-3x=0
• C. x \(\frac{d^2 y}{dx^2}\)–\(\frac{dy}{dx}\)=0
• D. \(\frac{d^2 y}{dx^2}-\frac{3dy}{dx}\)=0