The figure shows a Chromel-Alumel thermocouple, where the junction $A$ is held at temperature $T_{A},$ and a thermal emf $E_{1}$ is measured using an ideal voltmeter between the open ends $\text{B1}$ and $\text{B2},$ both held at temperature $T_{B}.$ Two identical copper wires are introduced between $\text{B1-C1}$ and $\text{B2-C2}$ as shown in the figure. When $\text{C1}$ and $\text{C2}$ are held at temperature $T_{C},$ the voltmeter reads a thermal emf $E_{2}.$ Then, _________
- $E_{1} < E_{2}$
- $E_{1} > E_{2}$
- $E_{1} = 2E_{2}$
- $E_{1} = E_{2}$