Step 1: Understanding the Question:
The sentence describes a claim that requires no further evidence.
We need to select an adjective that represents this characteristic of being obvious and requiring no additional proof.
Step 2: Key Concepts and Sentence Logic:
The key phrase in this sentence is ``required no further evidence''.
This indicates that the claim is inherently clear, obvious, and true on its own without needing external verification.
Step 3: Detailed Explanation:
• Option (C) - self-evident: This means clear or obvious without need of proof or explanation.
This fits the sentence context perfectly, explaining why no further evidence was necessary.
• Option (A) - doubtful: This means uncertain or unlikely, which would actually require a great deal of evidence to be accepted.
• Option (B) - ambiguous: This means open to more than one interpretation or having a double meaning, which would require clarification and evidence.
• Option (D) - equivocal: This means open to more than one interpretation, ambiguous, or uncertain, which also fails to match the logical requirements of the sentence.
Step 4: Final Answer:
Option (C) is the only logical choice that fits the semantic requirement of the sentence.