Biology 0610 · IGCSE · Pollution

Pollution — practice question

A farmer has a small pond on their farmland. In one year, most of the organisms in the pond die. In the following year, the farmer reduces the use of nitrate fertilisers and fewer organisms in the pond die. Which statement explains why this will help to increase the number of organisms living in the pond?

  • AThere is a decrease in dissolved oxygen due to an increase in decomposition.
  • BThere is a decrease in dissolved oxygen due to an increase in photosynthesis.
  • CThere is an increase in dissolved oxygen due to a decrease in decomposition.
  • DThere is an increase in dissolved oxygen due to a decrease in photosynthesis.

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