To measure the temperature coefficient of resistivity \(\alpha\) of a semiconductor, an electrical arrangement shown in the figure is prepared. The arm BC is made up of the semiconductor. The experiment is being conducted at \(25^{\circ} \mathrm{C}\) and resistance of the semiconductor arm is \(3 \mathrm{~m} \Omega\). Arm BC is cooled at a constant rate of \(2^{\circ} \mathrm{C} / \mathrm{s}\). If the galvanometer \(\mathrm{G}\) shows no deflection after \(10 \mathrm{~s}\), then \(\alpha\) is _______.

1. A \(-2 \times 10^{-2} \ { }^{\circ} \mathrm{C}^{-1}\)
2. B \(-1.5 \times 10^2\ { }^{\circ} \mathrm{C}^{-1}\)
3. C \(-1 \times 10^{-2}\ { }^{\circ} \mathrm{C}^{-1}\)
4. D \(-2.5 \times 10^{-2} \ { }^{\circ} \mathrm{C}^{-1}\)