The electric current flowing through a metallic wire is directly proportional to the potential difference V across its ends, provided its_____ remains the same.

Correct option is A

​$$\text{According to } \textbf{Ohm’s Law},$$​​

​$$V = IR$$

$$\text{where:}$$  $$V = \text{ Voltage (Potential Difference)}$$

$$I = \text{ Current}$$

$$R = \text{ Resistance (which depends on temperature)}$$

$$\textbf{Ohm’s Law} \text{ holds true only if the temperature remains constant.}$$

$$\text{If } \textbf{temperature changes}, \text{ the resistance of the wire changes, which affects the current.}$$​​​​​​​