Please answer my question?99

Equivalent circuit of the given circuit is shown which indicates that the three resistors are connected in parallel.

$$\begin{gathered} \frac{1}{R_{PQ}}=\frac{1}{r}+\frac{1}{2r}+\frac{1}{2r} \\ or R_{PQ} =\frac{r}{2} \end{gathered}$$

option a is correct

Regards