The most reactive metal is

Explanation: The following factors contribute to potassium's high reactivity:

• Potassium has a very low ionization enthalpy.
• It is the metal with the highest electropositivity and, as a result, the highest level of reactivity.
• It interacts violently with both air and water.

Final answer: Thus, we can say that option C is the correct answer. The most reactive metal is potassium.