Four substances, or categories of substances, present in water from a natural source are shown. 1 some metal compounds 2 plastics 3 dissolved oxygen 4 nitrates and phosphates from fertilisers and detergents. Which of the substances present in water from a natural source can be helpful to aquatic life?
- A1 and 3
- B1 and 4
- C2 and 3
- D2 and 4