[单选题]
A mass on a spring undergoes SHM. When the mass is at its:7jcmf1+ rlsn3d9peb maxir0 *dss5zq+ly mum displacement from e *z+yqrl0 sd5squilibrium, its instantaneous velocity
A. is maximum.
B. is less than maximum, but not zero.
C. is zero.
D. cannot be determined from the information given.
