Micrometer Error

A micrometer screw gauge with pitch of 0.5 mm and 50 divisions on circular scale is used to measure the diameter of a thin wire. Initially, when the gap is closed, the fourth division coincides with the reference line. Three readings show 46^th, 48^th and 44^th division coinciding with the reference line which is beyond 0.5 mm of the main scale. The (best) measured value is

(a) 0.46 mm (b) 0.94 mm (c) 0.92 mm (d) 1.00 mm