The Letters X and Y Represent Rectangular Coordinates $$x ^ { 2 } + 4 y ^ { 2 } = 4$$

Multiple Choice

The letters x and y represent rectangular coordinates. Write the equation using polar coordinates (r, θ) .
- $$x ^ { 2 } + 4 y ^ { 2 } = 4$$

A) $4 \cos ^ { 2 } \theta + \sin ^ { 2 } \theta = 4 \mathrm { r }$
B) $\cos ^ { 2 } \theta + 4 \sin ^ { 2 } \theta = 4 \mathrm { r }$
C) $r ^ { 2 } \left( \cos ^ { 2 } \theta + 4 \sin ^ { 2 } \theta \right) = 4$
D) $\mathrm { r } ^ { 2 } \left( 4 \cos ^ { 2 } \theta + \sin ^ { 2 } \theta \right) = 4$