A spring has natural length 40 cm and spring constant (500 ~N / m...

A spring has natural length 40 cm and spring constant (500 $\mathrm{~N}$/ $\mathrm{m}$). A block of mass 1 kg is attached at one end of the spring and others end of the spring is attached to the wall in horizontal position. The block release from the position, where the spring has length 45 cm then choose the correct statements : (A) The block will perform SHM of amplitude 5 cm (B) The block will have maximum velocity (50 $\sqrt{5} \mathrm{~cm}$/ $\mathrm{sec}$). (C) The block will have maximum acceleration at released position (D) The minimum P.E. of the spring will be zero