Correct temperature dependence of Resistivity of copper ( ρ ) is show…

The correct answer is Option (1)

Copper is a metal. When it is heated, its ions vibrate more, the electrons collide more often and the relaxation time \( \tau \) falls, so the resistivity \( \rho = m/(ne^{2}\tau) \) increases with temperature.

    \( \displaystyle \rho_T = \rho_0\left[1 + \alpha\,(T - T_0)\right], \quad \alpha \gt 0 \)

Over a wide range the rise is not exactly linear: the curve bends upward, as in Option (1).

NCERT (2026-27):
Temperature Dependence of Resistivity – “… For metals, α is positive. The relation of Eq. (3.26) implies that a graph of ρ_T plotted against T would be a straight line. At temperatures much lower than 0°C, the graph, however, deviates considerably from a straight line (Fig. 3.8).”