A ductile material having an endurance limit of 196 N/mm2 and the yield point at 294 N/mm2 is stressed under variable load. The maximum and minimum stresses are 147N/mm2 and 49N/mm2. The fatigue stress concentration factor is 1.32. The available factor of safety for this loading is
(a) 3.0 (b) 1.5
(c) 1.33 (d) 4.0