For a transmission line, if L. is the inductance and C is the capacitance per unit length of the line, then the surge impedance is expressed as:

Correct option is B

The surge impedance (also known as the characteristic impedance) of a transmission line is an important parameter in the analysis of wave propagation along the line. It is defined as the square root of the ratio of the inductance per unit length (L) to the capacitance per unit length (C).
The formula for surge impedance $$Z_0$$​ is given by:

​$$Z_0 = \sqrt{\frac{L}{C}}$$​​
Inductance (L) : The inductance per unit length of the transmission line, typically measured in henries per meter (H/m).
Capacitance (C) : The capacitance per unit length of the transmission line, typically measured in farads per meter (F/m).
Surge Impedance $$Z_0$$​ : This is the characteristic impedance of the transmission line and is expressed as the square root of the ratio of the inductance to the capacitance.
Given these definitions, the correct expression for the surge impedance is:

$$z_0 = \sqrt{\frac{L}{C}}$$​