Final answer:
Martin Luther incorporated nationalistic sentiments into his reform movement against Catholic practices to garner more support, leveraging the emotional power of shared German national pride.
Step-by-step explanation:
The subject question pertains to Martin Luther's strategic decision to incorporate nationalistic sentiments into his critiques of Catholic doctrine. Luther understood the power of the national identity and pride of the German people. Therefore, he incorporated this into his critiques to garner more support for his reform movement. This is, thus, represented by Option 3: Luther believed that appealing to national pride would garner more support for his reform movement. As he sought to break away from the widely accepted Catholic practices of the time, rallying the German people around common national pride provided a much stronger and emotionally charged basis for his reform movement than a purely religious critique would have.
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