Which type of capacitor is likely to be polarized?

Electrolytic capacitors are likely to be polarized because they are designed to operate with a specific polarity; they have a positive and a negative terminal. This polarization is necessary for their function, as they rely on a dielectric made of an oxide layer formed on the surface of the anode, which allows current to flow in only one direction. If an electrolytic capacitor is connected in reverse, it can fail or even explode due to the breakdown of the dielectric.

In contrast, non-polarized capacitors, such as film and ceramic capacitors, can be connected in either direction without risk of damage, making them inherently safe for applications that require AC signals. Variable capacitors also do not possess polarity, as their design is aimed at adjusting capacitance rather than maintaining a directional flow of charge. Thus, the unique construction and operating principles of electrolytic capacitors validate their status as the type most likely to be polarized.