Choose the correct complex sentence for the following compound sentence: “He tried his best, but he did not succeed.”

• A. Though he tried his best, he did not succeed.
• B. He tried his best, and he did not succeed.
• C. Despite trying his best, he did not succeed.
• D. He did not succeed, although he tried his best.

• Though he tried his best, he did not succeed.

Please select one of the options to reveal the correct answer.