Final answer:
Stalin maintained close control over the Soviet battlefronts and military reserves and political negotiations with Western powers. He strategically prepared for potential conflicts and played a crucial role in political negotiations during the war. His control also extended to the economic policy.
Step-by-step explanation:
Joseph Stalin played a crucial role in many aspects of the war and kept close control over more than one area. Among the choices given in your question, option (b) Soviet battlefronts and military reserves and option (c) Political negotiations with Western powers represent the areas where Stalin maintained close personal control. He prepared for possible conflicts by strategically building industrial bases, fostering alliances, and moving a significant proportion of the Soviet industrial base out of the enemy's reach. Additionally, Stalin was instrumental in political negotiations, as seen in conferences such as the Moscow and Potsdam Conferences. His control also extended to economic policy, such as the initiation of the Five-Year Plans and control on economic production during the civil war.
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