What is a free electron? A. An electron that has been freed from its parent atom B. An electron that costs nothing C. An electron that has no electrical charge D. An electron that has twice the amount of charge of a normal electron E. None of the above

The correct answer is A. An electron that has been freed from its parent atom.

A free electron is an electron that is not bound to an atomic nucleus. It can exist in a vacuum or in a material, such as a metal. Free electrons are important in many areas of physics and chemistry, including electricity, magnetism, and semiconductors.

Option B is incorrect because a free electron does not cost anything. It is a fundamental particle that is not created or destroyed.

Option C is incorrect because a free electron has a negative electrical charge.

Option D is incorrect because a free electron has the same amount of charge as a normal electron.

Option E is incorrect because there is no such thing as a free electron that has twice the amount of charge of a normal electron.