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
Correct Answer: Option B
B. Excess nitrates and phosphates → Massive algal growth → Lack of oxygen → Death of aquatic organisms