The correct option is C equal to the amplitude
We know that at mean position, velocity of particle is maximum.
⇒Hence kinetic energy associated with particle will be maximum at mean position.
Similarly,
vP=0 at the extreme position, where displacement of particle is equal to amplitude.
i.e y=±A
Now the total energy of particle is,
P.E+K.E=T.E
⇒P.E of vibrating particle will be maximum at extreme position, where K.E is minimum.
∴ option (c) is correct.