INSIGHT UPSC QUIZ

ANS. (A) 
The International Date Line (IDL) is an imaginary line on the surface of the Earth, that runs from the north to the South Pole and demarcates one calendar day from the next. It passes through the middle of the Pacific Ocean, roughly following the 180° longitude but it deviates to pass around some territories and island groups. From the north, the date line first deviates to the east of 180° to pass to the east of Russia’s Wrangel Island and the Chukchi Peninsula which is the easternmost part of Russian Siberia. The date line then passes through the Bering Strait between the Diomede Islands at a distance of 1.5 km from each island. The line then bends considerably southwest, passing west of St. Lawrence Island and St. Matthew Island. It then passes midway between Alaska’s Aleutian Islands and Russia’s Commander Islands before returning southeast to 180°. Thus, all of Siberia is to the west of the International Date Line, and all of Alaska is to the east of that line.