Find the Domain and Range and Describe the Level Curves

Multiple Choice

Find the domain and range and describe the level curves for the function f(x,y) .
-f(x, y) =

A) Domain: all points in the xy-plane; range: real numbers > 0; level curves: ellipses 3x² + 10y² = c

B) Domain: all points in the xy-plane except (0, 0) ; range: real numbers > 0; level curves: ellipses 3x² + 10y² = c

C) Domain: all points in the xy-plane; range: all real numbers; level curves: ellipses 3x² + 10y² = c

D) Domain: all points in the xy-plane except (0, 0) ; range: all real numbers; level curves: ellipses 3x² + 10y² = c