Final answer:
Charles V played a role as the ruler of the Holy Roman Empire by adopting policies of tolerance and arguing against the exclusivity of Catholicism and Protestantism.
Step-by-step explanation:
As the ruler of the Holy Roman Empire, Charles V played a significant role in the religious and political landscape of his time. However, his actions did not align with options c and d provided in the question. Instead, options a and b better describe his approach. Charles V adopted policies of tolerance and argued that neither Catholicism nor Protestantism could represent all Christians.
Charles V's policies of tolerance aimed to spare his empire from chaos by allowing rulers in the empire to establish their preferred religion within their lands. The 1555 Peace of Augsburg granted Lutheran rulers in the empire the right to establish Lutheranism as the official religion in their territories, ensuring religious harmony to some extent. This policy of toleration was an attempt to maintain stability and prevent further religious conflicts within the empire.