What is the average temperature of the surface water of the oceans?

Correct option is D

The worldwide average temperature of ocean surface water is approximately 17°C. This value is derived from global measurements of surface water across different latitudes and seasons. The temperature of ocean water varies depending on location:
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• Near the equator, where sunlight is more direct, ocean surface temperatures are higher (~30–36°C).
  
• At higher latitudes, particularly near the poles, surface temperatures can be as low as –2°C due to weak solar radiation.
  
• Overall, when averaged globally, the surface water temperature is 17°C.
  

Information Booster

• Ocean surface temperatures are highest near the equator due to direct solar radiation.
  
• Polar regions have the lowest surface temperatures due to less concentrated sunlight.
  
• Salinity affects freezing points: Seawater can remain liquid below 0°C because of dissolved salts.
  
• The average temperature of all ocean water (surface to deep ocean) is 3.5°C, much colder than the surface.
  
• Deep ocean water remains cold (~0–4°C) globally, regardless of latitude.