Step 1: Understanding the Sentence
This is a famous paradoxical statement attributed to Socrates (the Socratic paradox). The first blank needs an adjective to describe the man. The phrase "man alive" suggests a superlative degree (the most ________ of all men who are alive). The second blank needs a verb that agrees with the subject "I".
Step 2: Evaluating the Options
(A) Wiser, knowing: "Wiser" is a comparative adjective, not superlative. "Knowing" is a present participle, not a finite verb for the subject "I".
(B) Wise, knows: "Wise" is a positive adjective. The superlative is needed. "Knows" is the third-person singular form of the verb, which does not agree with "I".
(C) More wise, knows: "More wise" is comparative. "Knows" does not agree with "I".
(D) Wisest, know: "Wisest" is the superlative adjective, which fits the context of "man alive" perfectly. The verb "know" is the correct first-person singular form that agrees with the subject "I". This option fits both blanks correctly.
Step 3: Final Answer
The sentence requires the superlative form "Wisest" and the first-person verb "know". Therefore, option (D) is the correct answer.