Which sentence uses the restrictive clause correctly?

• A. The report that you wrote was helpful.
• B. The report, which you wrote, was helpful.
• C. The report, that you wrote, was helpful.
• D. The report you wrote was helpful.

Answer: (A)

Restrictive relative clauses identify exactly which noun we’re talking about, so they don’t use commas. In the sentence The report that you wrote was helpful, the clause that you wrote specifies which report is meant—the one you wrote. Because this detail is essential to the meaning, it stays tightly attached to the noun without any commas.

If you tried The report, which you wrote, was helpful, the clause would be nonessential information and would be separated by commas, changing the nuance to “in addition to the main report.” Putting a comma before that would also be incorrect in standard usage. The form The report you wrote was helpful is another correct way to express a restrictive relation by shortening the relative clause, but the version with that you wrote without commas is the clearest standard choice for a defining clause in this item.