Consider the following statements regarding the network shown in the figure

(i) The equivalent resistance of the network between A and B is independent of the value of R'
(ii) The equivalent resistance of the network between points A and B is 4 R/3
(iii) The current flowing through R' is zero

Which of the above statement(s) is/are correct?

(i), (ii) and (iii)

This is a balanced wheatstone bridge so no current will flow through the branch containing resistance R'.

Equivalent resistance is $R_{eq} = \frac{2R.4R}{2R + 4R} = \frac{4R}{3}$

$R_{eq}$ is independent of R'.