question_answer 28)

  The bluish colour of water in deep sea is due to (a) the presence of algae and other plants found in water                 (b) reflection of sky in water                 (c) scattering of light                 (d) absorption of light by the sea

Answer:

                  (C) The bluish colour of water in deep sea is due to scattering of light as the very fine particles in water scatter mainly blue light. The red, green, orange and yellow having longer wavelengths are absorbed more strongly by water than blue which has shorter wave length. So, when white light from the sun enters the sea, it is mostly the blue that gets returned.