Evaluate the effectiveness of three different Langflow prompt chains designed for generating marketing copy for a new SaaS product.  Each chain uses a different approach: Chain A focuses on keyword optimization, Chain B emphasizes benefit-driven language, and Chain C prioritizes concise and persuasive messaging.  For each chain, generate 5 marketing copy outputs.  The evaluation should assess the quality of the generated copy based on the following criteria: clarity, conciseness, persuasiveness, accuracy, originality, and SEO relevance (using relevant keywords provided in a separate document).  Provide a comparative analysis of the three chains, highlighting their strengths and weaknesses based on the evaluation criteria.  The final output should include a recommendation for the most effective Langflow prompt chain and justify your choice based on the evaluation results.  The output should be structured as a table summarizing the performance of each chain across the evaluation criteria, followed by a comparative analysis and final recommendation.