Explanation:

- The phrase "The defendant’s lawyer argued that his past offenses were ______ to this case" needs a word that indicates whether the past offenses are related to the current case or not.

- Option 1: Spacious – Means having a lot of room; unrelated to legal context or relevance.

- Option 2: Arrogant – Means having an exaggerated sense of one's own importance or abilities; doesn't fit the context of discussing relevance.

- Option 3: Contagious – Means capable of being transmitted by contact; inappropriate in discussing relevance.

- Option 4: Irrelevant – Means not connected or related to the matter at hand; best fits the context, as the lawyer argues the past offenses have nothing to do with the current case.

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