10. At the bottom of our world, there is a very icy and cold place. Antarctica is not just any landmass. In fact, it is a very big continent. It is the ... (FIVE) largest continent of this world.

The correct answer is 'fifth'. **Explanation:** The task is to transform the word in brackets so that it fits grammatically and contextually into the sentence. 'FIVE' needs to be changed to an ordinal number, 'fifth', to describe Antarctica's position among the continents in size.