Silicon is used to make:

Silicon is extensively used to make Semiconductors. Silicon's unique electrical properties, being neither a good conductor nor a good insulator, make it ideal for controlling electric current in electronic devices. It forms the fundamental material for transistors, integrated circuits, and microchips that power modern electronics.

• A Bus (B) in electronics refers to a communication system that transfers data between components, not a material.
• A Rod (C) is a shape or form, not a specific material or application for silicon.
• Therefore, "None of these" (D) is incorrect because semiconductors are a direct and primary application of silicon.