TOEFL Listening: TPO-TOEFL听力TPO - 7YT_AD7674GI81DMR$

What comparison does the professor make involving phosphorus and nitrogen? A. Sediment on the ocean floor contains more nitrogen than phosphorus B. The atmosphere contains more nitrogen than phosphorus C. Nitrogen requires more time to get recycled than phosphorus does D. Phosphorus is more important than nitrogen to the development of fish