What is meant by the phrase "distinction without a difference"?

The phrase "distinction without a difference" refers to a situation where a distinction is made between two categories or concepts, but in reality, that distinction does not yield any significant difference in meaning, application, or consequence. This can lead to confusion, as it appears that two separate ideas or classifications are being presented, but they do not actually diverge in any meaningful way.

Option B captures this concept accurately because it implies that a new category has been introduced without effectively outlining what sets it apart from existing categories. Thus, it points to a lack of substance in the differentiation being made, which aligns well with the essence of the phrase.

The other options do not accurately represent the concept. A highly specific and clear definition serves the opposite purpose by clarifying differences. A clear contrast suggests meaningful distinctions, which is not the case with "distinction without a difference." An explanation that resolves ambiguity implies clarity and understanding, which also contradicts the idea inherent in the phrase, where clarity fails to materialize despite the distinction made.