The region labeled with the number 4 on the map above is best known for being what type of landform? a. a plain b. an isthmus c. a plateau d. highlands

The correct answer is - D. highlands.

The region labeled with number 4 on the image is the eastern part of Siberia which is dominated by highlands. This is a geologically active region, where the Eurasian and North American plates collide. Because of the pressure they put on the land with their collision, the land has been lifting upwards, thus crating mountains in this part of the world.

The dominant land forms in this part of Siberia are the Kolyma Mountains and the Cherskiy Range.