The length of second's hand in watch is 1 cm. The change in velocity of its tip in 15 seconds is [MP PMT 1987]

• A.             Zero                                          
• B.             \[\frac{\pi }{30\sqrt{2}}\,\,cm/\sec \]
• C.             \[\frac{\pi }{30}\,\,cm/\sec \]
• D.                                         \[\frac{\pi \sqrt{2}}{30}\,\,cm/\sec \]