If the second derivative of negative of the equation of a curve is equal to the equation of that same curve, the curve is

Question: 

If the second derivative of negative of the equation of a curve is equal to the equation of that same curve, the curve is

Options:

• A. a paraboloid
• B. a sinusoid
• C. a cissoid
• D. an exponential

Answer Is:  B. a sinusoid