A particle performing SHM with a frequency of 5 Hz and amplitude 2 cm is initially at positive extreme position. The equation for its displacement (in metre) is

• A

  $\mathrm{x}=0.02\sin 10\mathrm{\pi t}$

• B

  $\mathrm{x}=0.02\sin 5\mathrm{\pi t}$

• C

  $\mathrm{x}=0.02\cos 10\mathrm{\pi t}$

• D

  $\mathrm{x}=0.02\cos 5\mathrm{\pi t}$