The polar equation of the circle with centre $\left(2, \frac{\pi}{2}\right)$ and radius 3 units is :

• A

  $r^2+4 r \cos \theta=5$
• B

  $r^2+4 r \sin \theta=5$
• Correct answer
  C

  $r^2-4 r \sin \theta=5$
• D

  $r^2-4 r \cos \theta=5$

Hence, the correct answer is option: 'C'.