Which of the following is a type of conduit commonly used in electrical installations?

The option concerning PVC (Polyvinyl Chloride) conduit is commonly used in electrical installations due to its versatility, resistance to corrosion, and ease of installation. PVC conduit is lightweight and can be easily cut and joined, making it a popular choice for various applications, especially in environments where moisture or chemicals might be a concern. It provides adequate protection for electrical wiring while being cost-effective compared to other types of conduit.

Metal conduit is another option widely utilized in electrical installations; however, it is not the only type specifically highlighted here. Flex duct, primarily associated with HVAC systems, does not apply to electrical installations. Insulated wire, while essential in electrical work, is not classified as a conduit. Thus, the choice of PVC conduit stands out as a widely accepted and practical option for electrical conduits, addressing specific needs in many installation scenarios.