Final answer:
The Tibetan Plateau is the youngest and highest plateau in the world, known as "the Roof of the World," with an elevation of over three miles above sea level and an average elevation of 15,000 feet. The correct answer to which physiographic region of East Asia is the youngest and highest plateau in the world is B) Tibetan Plateau.
Step-by-step explanation:
The Tibetan Plateau is often known as "the Roof of the World" and stands over three miles above sea level. It is surrounded by some of the highest mountain ranges, including the Himalayas where Mount Everest, the tallest peak on Earth, is located. Created by the tectonic activity, specifically the Indian plate pushing against the Eurasian plate, it features an average elevation of 15,000 feet, making it the highest plateau region globally. The Tibetan Plateau's landscape is mostly rocky and barren, with scant precipitation, sometimes in the form of hailstorms.
Mainly characterized by a type H climate, the plateau's harsh conditions contribute to its sparse population, with the significant exception of river valleys, such as around Lhasa, the largest city in the region. This plateau is of significant geologic and ecological importance due to its high elevation and its role in affecting regional climate conditions.