Which are the two main sources of dissolved oxygen in the ocean? A) surface air and ocean plants B) Warm water vents and Earth’s core
C) Underwater volcanoes and earthquakes D) Animal respiration and decomposition

The infrared (ir) and the ultraviolet(uv) represent the two extremities of the visible spectrum (400-700nm). while ir represents electromagnetic radiation with wavelengths longer than those of visible light, uv represents wavelengths shorter than visible light