A cylinder of 25 mm diameter and 100 mm length is turned with a tool, for which the relation VT0.25 = 55 is applicable. The cutting velocity is 22m/min. For tool feed of 0.046 mm/rev, the number of tool regrinds required to produce 425 cylinders is
(a) 12 (b) 22 (c) 43 (d) 85