Express the Area of the Region Bounded by the Given $\frac { x } { 4 } + \frac { y } { 5 } = 1 , \frac { x } { 5 } + \frac { y } { 4 } = 1$

Multiple Choice

Express the area of the region bounded by the given line(s) and/or curve(s) as an iterated double integral.
-The lines $\frac { x } { 4 } + \frac { y } { 5 } = 1 , \frac { x } { 5 } + \frac { y } { 4 } = 1$ , and $x = 0$

A) $\int _ { 0 } ^ { 20 / 9 } \int _ { 5 - 5 x / 4 } ^ { 4 - 4 x / 5 } d y d x$
B) $\int _ { 0 } ^ { 20 / 9 } \int _ { 4 - 4 x / 5 } ^ { 5 - 5 x / 4 } d y d x$
C) $\int _ { 0 } ^ { 9 } \int _ { 5 - 5 x / 4 } ^ { 4 - 4 x / 5 } d y d x$
D) $\int _ { 0 } ^ { 9 } \int _ { 4 - 4 x / 5 } ^ { 5 - 5 x / 4 } d y d x$