UPSC CDS English Reading Comprehension Part 2 Questions

Passage

  For many years, ship captains navigating the waters of Antarctica have been intrigued by sightings of emerald icebergs. Scientists have now explained their mystery There icebergs are turned upside down. Icebergs are blocks of ice that have broken off huge slabs of frozen snow called ice shelves. Their green appearance results from sea water that has frozen at the bottom over hundreds of years. The frozen sea water has dissolved organic matter which gives it a yellow tone and the fresh water ‘ice shelf’ above has a blue tinge. When the iceberg turns upside down, it appears green through the visual mix of yellow with the blue from below.