Question: Which mountain, Muztagh Tower or K2,  is the highest point of the Karakoram range and the highest point in both Pakistan and Xinjiang?

Context paragraphs:
Serra da Estrela: Serra da Estrela (] , "Star Mountain Range") is the highest mountain range in Continental Portugal.  Together with the Serra da Lousã it is the westernmost constituent range of the Sistema Central and also one of the highest in the system.  It includes mainland Portugal's highest point at 1993 m above mean sea level (although the summit of Mount Pico in the Portuguese Azores islands is higher).  This point is not a distinctive mountain summit, but rather the highest point in a plateau, being known as Torre ("Tower" in English).  Torre is an unusual summit in that it is accessible by a paved road.  The peak has a topographic prominence of 1204 m and its parent peak is Pico Almanzor, in Spain.

Sarpo Laggo Glacier: The Sarpo Laggo Glacier ("Sarpo Laggo": young husband) is a glacier in the autonomous region Xinjiang of China, in the Karakoram mountain range of the Himalayas.  It lies north of the Baltoro Muztagh range.  It could be reached from the Baltoro glacier on the Pakistani side of the Karakorams via the "Old Muztagh Pass" northeast of the Trango Towers.  It is however easier to approach the glacier from the Chinese side, starting a long hike at Kashgar on the Karakoram Highway and finally passing K2's northern base camp.

Batura Sar: Batura Sar (Urdu: بتورا سر‎ ), also referred to as Batura I, is the 25th highest mountain on earth and the 10th highest in Pakistan.  It is the highest peak of the Batura Muztagh, which is the westernmost subrange of the Karakoram range.  It forms the apex of the Batura Wall, which is a continuously high part of the backbone of the Batura Muztagh.

Trango Towers: The Trango Towers (Urdu: ‎ ) are a family of rock towers situated in Gilgit-Baltistan, in the north of Pakistan.  The Towers offer some of the largest cliffs and most challenging rock climbing in the world, and every year a number of expeditions from all corners of the globe visit Karakoram to climb the difficult granite.  They are located north of Baltoro Glacier, and are part of the Baltoro Muztagh, a sub-range of the Karakoram range.  The highest point in the group is the summit of "Great Trango Tower" at 6,286 m (20,623 ft), the east face of which features the world's greatest nearly vertical drop.

Hispar Muztagh: Hispar Muztagh is a sub-range of the Karakoram mountain range.  It is located in the Gojal region of Gilgit-Baltistan, Pakistan, north of Hispar Glacier, south of Shimshal Valley, and east of the Hunza Valley.  It is the second highest sub-range of the Karakoram, the highest being the Baltoro Muztagh.  The highest mountain in the range is Distaghil Sar (7,885m/25,869 ft).

Steel Mountain: Steel Mountain is the highest point in Boise National Forest and the second highest point in the Boise Mountains at an elevation of 9730 ft .  It is located 17.08 mi from Two Point Mountain, the highest point in the range and its line parent, giving it a prominence of 2188 ft .

Muztagh Tower: Muztagh Tower (also: Mustagh Tower; "Muztagh": ice tower), is a mountain in the Baltoro Muztagh, part of the Karakoram range in Baltistan on the border of the Gilgit–Baltistan region of Pakistan and the Xinjiang Uyghur Autonomous Region of China.  It stands between the basins of the Baltoro and Sarpo Laggo glaciers.

Karakoram: The Karakoram, or Karakorum is a large mountain range spanning the borders of Pakistan, India, and China, with the northwest extremity of the range extending to Afghanistan and Tajikistan.  It is located in the regions of Gilgit–Baltistan (Pakistan), Ladakh (India), and southern Xinjiang (China), and reaches the Wakhan Corridor (Afghanistan).  A part of the complex of ranges from the Hindu Kush to the Himalayan Range, it is one of the Greater Ranges of Asia.  The Karakoram is home to the four most closely located peaks over 8000m in height on earth: K2, the second highest peak in the world at 8611 m , Gasherbrum I, Broad Peak and Gasherbrum II.

K2: K2 (Urdu: ‎ ), also known as Mount Godwin-Austen or Chhogori (Balti and Urdu: ‎ ), is the second highest mountain in the world, after Mount Everest, at 8611 m above sea level.  It is located on the China-Pakistan border between Baltistan, in the Gilgit-Baltistan region of northern Pakistan, and the Taxkorgan Tajik Autonomous County of Xinjiang, China.  K2 is the highest point of the Karakoram range and the highest point in both Pakistan and Xinjiang.

Piz Bernina: Piz Bernina or Pizzo Bernina (] ) is the highest mountain in the Eastern Alps, the highest point of the Bernina Range, and the highest peak in the Rhaetian Alps.  It rises 4,048.6 m (13,283 ft) and is located south of Pontresina and near the major Alpine resort of St. Moritz, in the Engadin valley with the massif partially in Italy.  It is also the most easterly mountain higher than 4,000 m in the Alps, the highest point of the Swiss canton of Graubünden, and the fifth-most prominent peak in the Alps.  The minor summit (4,020 m ) known as La Spedla is the highest point in the Italian Lombardy region.

Supporting paragraphs: Muztagh Tower K2
Answer: K2