Question

which element is mined, processed, and concentrated into fuel rods to be used at nuclear power plants?
a thorium
b helium
c uranium
d potassium

Explanation:

Uranium is mined, processed, and concentrated into fuel rods for use in nuclear power - plants. Thorium can also be used in some nuclear processes but is not as commonly used as uranium for fuel rods. Helium is a noble gas and not used as nuclear fuel. Potassium is a common element in many chemical and biological processes but not related to nuclear fuel rods.

Answer:

C. Uranium