A

In a Wheatstone bridge, the bridge is said to be balanced when the ratio of the resistances in one pair of opposite arms is equal to the ratio of the resistances in the other pair. Mathematically, this can be expressed as:
$$\frac{R_1}{R_2} = \frac{R_3}{R_4}$$
where \(R_1\) and \(R_2\) are the resistances in one branch, and \(R_3\) and \(R_4\) are the resistances in the other branch.
When the resistances in arms Q and S are interchanged, the ratios will change, leading to:
$$\frac{R_1}{R_2} \neq \frac{R_4}{R_3}$$
Consequently, the bridge will not be balanced anymore, and the galvanometer will show a deflection as current flows through it.
Therefore, the correct answer is that the network is not balanced.