Which of these is a FALSE statement?

The Wheatstone bridge is most sensitive when all the four resistances are of the same order.

In a balanced Wheatstone bridge, interchanging the positions of galvanometer and cell affects the balance of the bridge

Kirchhoff's first law (for currents meeting at a junction in an electric circuit) expresses the conservation of charge.

The rheostat can be used as a potential divider.