Which of the following does not lead to an increase in phytoplankton reproduction?

Phytoplankton use nutrients, sunlight, and carbon dioxide to grow and reproduce, so increases in those resources can support more reproduction. Oxygen is a product of photosynthesis rather than a resource that typically drives phytoplankton growth. Therefore, increased oxygen levels do not lead to an increase in phytoplankton reproduction.

AI-written and checked against the verified answer.