Correct option is (a) Sheep’s foot
The explanation: Sheep’s foot rollers consist of hollow Steel cylinder or cylinders, each about 1.20 m long and 1.20 m in diameter with 180 mm to 230 mm projections extending out from the curved surface of the cylinder. These projections are made of steel and they resembles Sheep’s feet and are arranged in row round the cylinders, the projections in successive rows being staggered.