Meter Bridge Error

In a meter bridge experiment, the resistance to be measured is connected in the right gap and a known resistance in the left gap has a value of 50±0.2 Ω when the null point is judged to be at 60±0.2 cm. The student notes that the ends of the bridge wire are not at 0.0 cm and 100.0 cm respectively of the scale and makes a guess that they may be somewhere within 0.2 cm beyond the scale ends. The value of the unknown resistance should be expressed as

(a) 33.33±1 Ω (b) 75±1 Ω (c) 75.0±0.9 Ω (d) 33.4±0.5 Ω