Which of the following substances has the best insulation performance?

The choice of Bakelite as the substance with the best insulation performance is based on its specific properties. Bakelite is a type of phenolic resin that exhibits excellent electrical insulating characteristics. This makes it particularly useful in applications where preventing the flow of electricity is crucial, such as in electrical components and housings.

Bakelite is thermosetting, meaning it doesn't melt upon heating but rather retains its shape and insulating properties even under high temperatures. Its structure provides a robust barrier to electricity, contributing to its effectiveness as an insulator. This high thermal stability, combined with its low electrical conductivity, makes Bakelite superior in insulation performance compared to the other materials listed.

While wood, plastic, and glass all have insulating properties to varying degrees, they do not match the effectiveness of Bakelite in terms of electrical insulation. Wood is porous and can absorb moisture, which can reduce its insulating capacity. Plastic does provide good insulation but may not withstand high temperatures as effectively as Bakelite. Glass is a good insulator as well but is generally more brittle and can break under stress, making it less durable than Bakelite for consistent use in electrical applications.