[单选题]
A mass on a spring undergoes SHM. When the mass is 7gn4a c9 qbr/ratv9( bhq,1uc p9oqm1 bq maximum displacement from equilibrium, its instantaneous acceleration hqvub91qcbmoq1p( , 9
A. is a maximum.
B. is less than maximum, but not zero.
C. is zero.
D. cannot be determined from the information given
