Which one is the correct diagram for Resistivity vs Temperature for Metals

Explanation:
In metals, there are a large number of free electrons which helps in electric conduction. As temperature increases, collision between free electrons increases. And as a result, resistivity increases.
For metals, relation between resistivity and temperature  is given as,
T=01+T-T0
From the above equation, it is clear that the relation between resistivity and temperature is a straight line.

Final answer:
Hence, the correct diagram is figure 1.