Which of the following orders correctly represents the trend in eutrophication?

• A.Lack of oxygen → Death of aquatic organisms → Massive algal growth
• B.Excess nitrates and phosphates → Massive algal growth → Lack of oxygen → Death of aquatic organisms
• C.Heavy mineralization → Lack of oxygen → Massive algal growth
• D.Excess nitrates and phosphates → Lack of oxygen → Massive algal growth → Death of aquatic organisms