Which of the following statements about insulating materials is correct?a. Insulators can be used to increase the amount of current that can flow through a resistor without increasing its temperature. b.The electric field from a charged object is able to penetrate through an insulating material. c.Insulating materials exhibit a linear relationship between voltage and current. d.Silver and copper are good insulators.

a.Insulators can be used to increase the amount of current that can flow through a resistor without increasing its temperature.

Explanation:

A conductor has low resistance, while an insulator has much higher resistance. Devices called resistors control amounts of resistance into an electrical circuits. Electric charges inside an insulator are bound to the individual atoms or molecules, not being able to move inside the material.

When you turn up the resistance, the electric current flowing through the circuit is reduced

Ohm's law:

V = I * R

R = V/I

An Ohmic conductor would have a linear relationship between the current and the voltage. With non-Ohmic conductors, the relationship is not linear. Most metals are good conductors example silver, copper etc.