Explanation: Intermontane basins are depressions or valleys that are surrounded by mountains or hills. In the context of Mizoram, these basins, such as the Aizawl Basin, are significant geographical features that play a crucial role in the region's topography and human activities.
The primary characteristic of intermontane basins in Mizoram is their relatively flat terrain compared to the surrounding hills. This flatness is a result of the geological processes that have shaped the landscape over time. The basins are formed when the surrounding mountains or hills erode and deposit sediments in the lower areas, creating a relatively flat surface.
The flat terrain within these basins is highly advantageous for human habitation and agricultural activities. The flat land is easier to cultivate and build on compared to the steep slopes of the surrounding hills. This makes the basins ideal locations for settlements, farms, and other human activities. The Aizawl Basin, for example, is home to the capital city of Mizoram, Aizawl, which is built on the relatively flat terrain of the basin.
It is important to note that while the surrounding hills are rugged and steep, the intermontane basins themselves are not. The basins provide a more stable and accessible environment for human activities, which is why they are often the sites of major settlements and agricultural lands.
In contrast, the other options do not accurately describe the primary characteristic of intermontane basins in Mizoram. Option A suggests that the basins are extremely rugged and unsuitable for habitation, which is incorrect because the basins are relatively flat. Option B states that the basins are primarily covered by dense forests with no human settlement, which is also incorrect because the basins are often cleared for cultivation and habitation. Option D suggests that the basins are major sources of mineral extraction, which is not their primary characteristic.
In summary, the primary characteristic of intermontane basins in Mizoram, such as the Aizawl Basin, is their relatively flat terrain compared to the surrounding hills, making them suitable for cultivation and habitation. This flatness is a result of geological processes and provides a stable and accessible environment for human activities.