In a Wheatstone bridge all the four arms have equal resistance \( \mathrm{R} \). If the resistan...

In a Wheatstone bridge all the four arms have equal resistance \( \mathrm{R} \). If the resistance of galvanometer arm is also \( \mathrm{R} \), the equivalent resistance of combination is
(a) \( 2 \mathrm{R} \)
(b) \( \mathrm{R} / 4 \)
(c) \( \mathrm{R} / 2 \)
(d) \( \mathrm{R} \)