On Earth, plasma exists in the ionosphere, in flames, and in chemical and nuclearexplosions. Matter in a controlled thermonuclear reactor also exists in a plasma state.Plasma is most like a gas. However, it differs from un-ionized gas in that it is a goodconductor of electricity and heat. Scientists hope to understand the occurrence of plasmain nature and to harness it as an inexpensive energy source.Based on the passage, how can the cost of developing thermonuclear power with plasmabe defended?A. It is almost perfected already.B. Current nuclear power is too dangerous.C. A plasma power source can be used without special equipment.D. It can provide an inexpensive power source.OE. It is applicable to all technologies.