question_answer 26)

  The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light (a) is scattered the most by smoke or fog (b) is scattered the least by smoke or fog (b) is absorbed the most by smoke or fog (d) moves fastest in air

Answer:

                  (B) The danger signals installed at the top of tall buildings are red in colour because among all other colours, red colour is scattered the least by smoke or fog. This is primarily because wavelength of red colour is the largest. Thus it can be easily seen from a distance.