Step 1: Understanding the Question:
This question tests knowledge of nitrogen fertilizers and their additives.
Step 2: Detailed Explanation:
Benzoquinones and quinones are nitrification inhibitors.
They inhibit the conversion of ammonium to nitrate, reducing nitrogen losses.
Slow-release N fertilizers (A): Not correct.
Urease inhibitors (C): Not correct.
Thus, the correct answer is nitrification inhibitors.
Step 3: Final Answer:
Thus, benzoquinones and quinones are nitrification inhibitors, which corresponds to option (B).
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