Final answer:
Plutonium is a silver-white, lustrous, radioactive metal. Its oxide is used as fuel in nuclear power plants and in atomic warheads. It is an actinide element with valuable radioactive properties.
Step-by-step explanation:
The subject of this question is Chemistry, as it relates to the properties and uses of a specific metal.
The answer to the question is b. plutonium. Plutonium is a silver-white, lustrous, radioactive metal. Its oxide is used as fuel in nuclear power plants and in atomic warheads. Plutonium is an actinide element and is valuable primarily because of its radioactive properties, which make it useful in various applications.
Examples of the uses of plutonium include its employment in nuclear weapons and in nuclear power plants for generating electrical energy. Plutonium-239 is produced as a decay product of uranium isotopes.