Task: Question Answering
Input (English): Context: The Aldan River is the second-longest tributary of the Lena River in the Sakha Republic in eastern Siberia. The river is long, of which around is navigable. It was part of the River Route to Okhotsk. In 1639 Ivan Moskvitin ascended the Aldan and Maya Rivers and crossed to the Ulya River to reach the Sea of Okhotsk., Ulya River is a river in northern Khabarovsk Krai in Russia. The length of the river is , the area of its drainage basin is . The Ulya originates in the Dzhugdzhur Mountains, flows northeast parallel to the coast and turns east to reach the Sea of Okhotsk about southwest of Okhotsk. It freezes up in late October through early November and remains icebound until May. The first Russian to reach the Pacific Ocean was Ivan Moskvitin who sailed down the Ulya and wintered near its mouth in 1639. Vasili Poyarkov reused his huts in 1646. The Ulya was one of the water routes to and from Okhotsk. From its tributaries either the Lama Portage or the Alachak Portage led to the Mati River which flows north to the Maya River, which leads to the Aldan River and then Lena River to Yakutsk., "Main Stem" is 1942 instrumental by Duke Ellington and His Famous Orchestra. Although recorded in 1942, the single would not be released until 1944 where it was Duke Ellington's last of four number one's on the Harlem Hit Parade. "Main Stem" also peaked at number twenty on the pop chart., The Amur River (Even: , "Tamur" ) or Heilong Jiang ("Black Dragon River" "Black Water") is the world's tenth longest river, forming the border between the Russian Far East and Northeastern China (Inner Manchuria). The largest fish species in the Amur is the kaluga, attaining a length as great as ., Bodaybo is a town and the administrative center of Bodaybinsky District in Irkutsk Oblast, Russia, located on the Vitim River at its confluence with the Bodaybo River, located from Irkutsk, the administrative center of the oblast. Population: 12,800 (1968)., A drainage basin or catchment basin is an extent or an area of land where all surface water from rain, melting snow, or ice converges to a single point at a lower elevation, usually the exit of the basin, where the waters join another body of water, such as a river, lake, reservoir, estuary, wetland, sea, or ocean. Thus if a tributary stream joins a brook that in turn joins a small river which is a tributary of a larger river, there is a series of successively larger (and lower elevation) drainage basins. For instance, the Missouri and Ohio rivers are within their own drainage basins and also within the drainage basin of the Mississippi River., The Olyokma River ( Russian :  Olëkma ; Sakha :  Ölüöxüme ) is a tributary of the Lena in eastern Siberia . To the west is the Vitim River , to the south the Shilka River and Amur River and to the east , the upper Aldan River . Its right branch , the Tungir River , leads to a portage to the Shilka . Yerofey Khabarov used this route to travel from the Lena to the Amur . Other tributaries are the Nyukzha and the Chara Rivers . The river is approximately 1,320 kilometers ( 820 miles ) long . The Olyokma rises in the south of the Yablonovy Mountains , west of Mogocha . It flows north through remote terrain before joining the Lena near Olyokminsk ., Maya River (or ) is a river in Khabarovsk Krai and Sakha, Russia. It is a right tributary of the Aldan River of the Lena basin. The length of the river is . The area of its basin . The Maya River freezes up in late October and stays under the ice until May. The Yudoma River is one of the biggest tributaries of the Maya. The river is navigable up to upstream from its mouth., Okhotsk is an urban locality (a work settlement) and the administrative center of Okhotsky District of Khabarovsk Krai, Russia, located at the mouth of the Okhota River on the Sea of Okhotsk. Population: , A tributary or affluent is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage basin of its surface water and groundwater, leading the water out into an ocean., Transbaikal, Trans-Baikal, Transbaikalia, or Dauria ("Dauriya") is a mountainous region to the east of or "beyond" (trans-) Lake Baikal in Russia., Yerofey Pavlovich Khabarov or Svyatitsky (the first name is often spelled  (Yarofei) in contemporary accounts; 1603  after 1671), was a Russian entrepreneur and adventurer, best known for his exploring the Amur river region and his attempts to colonize the area for Russia. For background see Russian-Manchu border conflicts., The Sea of Okhotsk is a marginal sea of the western Pacific Ocean, lying between the Kamchatka Peninsula on the east, the Kuril Islands on the southeast, the island of Hokkaido to the south, the island of Sakhalin along the west, and a long stretch of eastern Siberian coast (the Shantar Sea) along the west and north. The northeast corner is the Shelikhov Gulf. The sea is named after Okhotsk, the first Russian settlement in the Far East., The Russian Far East is the Russian part of the Far East, i.e. the extreme east parts of Russia, between Lake Baikal in Eastern Siberia and the Pacific Ocean. The Far Eastern Federal District, which covers this area, borders with the Siberian Federal District to the west. The Far Eastern Federal District has land borders with the People's Republic of China and North Korea to the south west and maritime borders with Japan and the American state of Alaska. Although traditionally considered part of Siberia, the Russian Far East is categorized separately from Siberia in Russian regional schemes (and previously during the Soviet era when it was called the Soviet Far East)., Lake Baikal (, "Baygal nuur", etymologically meaning, in Mongolian, "the Nature Lake") is a rift lake in Russia, located in southern Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast., The Shilka is a river in Zabaykalsky Krai, south-eastern Russia. It has a length of . It originates as a confluence of the Onon and Ingoda rivers. Its confluence with the Ergune on the Russia-China border gives rise to the Amur River. The river is navigable for its entire length. The name derives from Evenki "shilki" 'narrow valley.', Vitim River (Russian and ; ) is a major tributary of the Lena River. With its source east of Lake Baikal, the Vitim flows north through the Transbaikal Mountains and the town of Bodaybo. The river peaks in June and freezes from November to May. It is navigable from the Lena to Bodaybo. Upstream, tugs can haul barges as far as the Baikal Amur Mainline (BAM), but this is becoming rare. Formerly, because of its swift current, goods were hauled overland from Chita to a place called Romanovka. There boats were built, floated down the river, and broken up at their destination. This lasted until the late 1940s. The Vitim is an excellent place for adventure rafting, but is rarely visited because of its isolation., The Lena ( "Zülge" "Zülxe" "Ölüöne") is the easternmost of the three great Siberian rivers that flow into the Arctic Ocean (the other two being the Ob and the Yenisei). It is the 11th longest river in the world and has the 9th largest watershed. It is also the 3rd largest river in Asia. It is the largest among the rivers whose watershed is entirely within the Russian territorial boundaries., Ivan Yuryevich Moskvitin (? - after 1647) was a Russian explorer, presumably a native of Moscow, who led a Russian reconnaissance party to the Sea of Okhotsk, becoming the first Russian to reach the Pacific Ocean., A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases a river flows into the ground and becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to using names such as stream, creek, brook, rivulet, and rill. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities a stream is defined by its size. Many names for small rivers are specific to geographic location; examples are "run" in some parts of the United States, "burn" in Scotland and northeast England, and "beck" in northern England. Sometimes a river is defined as being larger than a creek, but not always: the language is vague., Subject: olyokma river, Relation: mouth_of_the_watercourse, Options: (A) aldan river (B) amur (C) arctic ocean (D) lake baikal (E) lena river (F) main (G) maya river (H) mississippi river (I) ob (J) sea (K) sea of okhotsk (L) vitim river (M) yenisei
Output (English): lena river