Question

what environmental concern related to climate change could result in lower dissolved oxygen levels in water? rising water salinity increasing biodiversity warmer water temperatures decreased water pollution

Explanation:

To solve this, we analyze each option:

• Rising water salinity: Salinity mainly affects water density/osmosis, not dissolved oxygen (DO) levels directly related to climate - change - induced DO drop.
• Increasing biodiversity: Higher biodiversity usually implies a balanced ecosystem; more species might even help maintain or increase DO in some cases (e.g., more photosynthetic organisms), so it's not a cause of lower DO.
• Warmer water temperatures: As water temperature rises (a result of climate change), the solubility of oxygen in water decreases. Warmer water holds less dissolved oxygen, so this is a valid cause.
• Decreased water pollution: Less pollution would likely improve water quality and could increase DO levels (e.g., less organic matter to decompose and consume oxygen), so it's not a cause of lower DO.

Answer:

C. warmer water temperatures (assuming the options are labeled A: rising water salinity, B: increasing biodiversity, C: warmer water temperatures, D: decreased water pollution)