What is 'Tokamak' ?
- A. An Israeli radar system
- B. An American anti-missile system
- C. A defence collaboration between Japan and South Korea
- D. A device used in nuclear-fusion research for magnetic confinement of plasma
Explanation
A tokamak is a doughnut-shaped device that uses magnetic fields to confine extremely hot plasma for nuclear-fusion research. Magnetic confinement prevents the plasma from directly touching the vessel walls.