A disc can roll without slipping , with out applying any external force on a <br> 1) rough inclined plane <br> 2) smooth inclined plane <br> 3) rough horizontal surface <br> 4) smooth horizontal surface

Question

$ a)\; 1,2\; and\; 3 \\ b) 1,3\; and\; 4 \\ c) 2,3\; and\; 4 \\ d)\; 1,2\; and\; 4 $