Find the Domain and Range and Describe the Level Curves $x y$

Multiple Choice

Find the domain and range and describe the level curves for the function f(x,y) .
-f(x, y) = ln (5x + 4y)

A) Domain: all points in the $x y$ -plane; range: all real numbers; level curves: lines $5 x + 4 y = c$
B) Domain: all points in the xy-plane satisfying $5 x + 4 y \geq 0$ ; range: all real numbers; level curves: lines $5 x + 4 y = c$
C) Domain: all points in the $x y$ -plane satisfying $5 x + 4 y > 0$ ; range: all real numbers; level curves: lines $5 x + 4 y = c$
D) Domain: all points in the $x y$ -plane satisfying $5 x + 4 y > 0$ ; range: real numbers $z \geq 0$ ; level curves: lines $5 x + 4 y = c$