On which of the following factors does the resistivity of a material depend ?

The resistivity $$ \rho $$ of a material depends on multiple factors, and all of the mentioned options contribute to it:

Resistance of the conductor: The resistivity is directly related to the resistance through the formula $$ R = \rho \frac{L}{A} $$, where $$ R $$ is the resistance, $$ \rho $$ is the resistivity, $$ L $$) is the length of the conductor, and $$ A $$ is the area of the conductor section.
Area of the conductor section: The area of the conductor section $$( A )$$ is present in the denominator of the resistance formula. As the area increases, the resistance decreases, and vice versa.
Length of the conductor: The length of the conductor $$( L )$$ is also present in the numerator of the resistance formula. As the length increases, the resistance increases, and vice versa.

Therefore, the correct answer is Option D: All of the above.