Geographers and historians have traditionally held the view that Antarctica was first sighted around 1820, but some sixteenth-century European maps show a body that resembles the polar landmass, even though explorers of the period never saw it. Some scholars, ttherefore, argue that the continent must have been discovered and mapped by the ancients, whose maps are known to have served as models for the European cartographers. Which of the following, if true, is most damaging to the inference drawn by the scholars? ['Ancient philosophers believed that there had to be a large landmass at the South Pole to balance the northern continents and make the world symmetrical.', 'Between 3, 000 and 9, 000 years ago, the world was warmer than it is now, and the polar landmass was presumably smaller.', 'There are only a few sixteenth-century global maps that show a continental landmass as the South Pole.', 'The question of who first sighted Antarctica in modern times is still much debated, and no one has been able to present conclusive evidence.']