Step 1: Henry Fayol's profession.
Henry Fayol was a French management theorist, and his contributions are fundamental in the study of management. He is best known for his development of the administrative theory of management. Fayol was an engineer by training and worked as an accountant and manager in his career.
Step 2: Analyzing the options.
(A) Scientist: Incorrect. Fayol was not a scientist.
(B) Mining Engineer: Incorrect. Fayol was not specifically a mining engineer.
(C) Accountant: Correct. Fayol was trained as an engineer and worked as an accountant.
(D) Production Engineer: Incorrect. Fayol's career did not center solely on production engineering.
Step 3: Conclusion.
The correct answer is (C) Accountant, as Henry Fayol was an accountant by profession.