Answer:
C.
Step-by-step explanation:
To solve the problem we need to use the concept related to Centripetal Force. According to Newton's second law, for an acceleration to occur, a force must act in the direction of that acceleration. Thus, if we consider a particle of mass m, in uniform circular motion, it will be subjected to a centripetal force given by:

Where,
m= mass
v= velocity
r = radius
Re-arrange for the radius

Our values are given by,



Replacing we have that


Therefore the correct answer is C.