Transform the given rectangular equation into a polar equation.
$y^2=117x$

• A. $r=\frac{117\sin \theta }{{\cos }^2\theta }$
• B. $r=117{\cos }^2\theta$
• C. $r=\frac{117}{{\sin }^2\theta }$
• D. $r=\frac{117\cos \theta }{{\sin }^2\theta }$

Answer: (D)