Select the correct statement.

The $I-V$ characteristics of a metal wire at two different temperatures ($T_{1}$ and $T_{2}$) are given in the adjoining figure. Here,we can conclude that:

Of the following graphs,the one that correctly represents the $I-V$ characteristics of an 'Ohmic device' is:

The variation of current $(i)$ passing through a conductor as the voltage $(V)$ applied across its ends is varied is shown in the adjoining diagram. If the resistance $(R)$ is determined at the points $A, B, C$ and $D$,we will find that

Assertion : Ohm's law is applicable for all conducting elements.
Reason : Ohm's law is a fundamental law.

The current $(I)$ and voltage $(V)$ graphs for a given metallic wire at two different temperatures $T_1$ and $T_2$ are shown in the figure. It is concluded that