During an experiment with ametre bridge, the galvanometer shows a null point when the jockey is pressed at 40.0 cm using a standard resistance of $$90 Ω$$,as shown in the figure. The least count of the scale used in the metre bridge is 1 mm. The unknown resistance is

A

$$60 \pm 0.15Ω$$

B

$$135 \pm 0.56Ω$$

C

$$60 \pm 0.25Ω$$

D

$$135 \pm 0.23Ω$$