Physical Features of India

Antecedent rivers keep cutting their old course even after mountain uplift. For exams remember deep gorges of Indus and Brahmaputra.

Young fold mountains commonly have geological activity and steep slopes. For exams link the Himalayas with earthquakes and landslides.

Glaciers of Himadri feed many Himalayan rivers. For exams remember the glacier and perennial river link.

Dun valleys are sedimentary valleys located between mountain ranges. For exams keep Dehradun as the main example.

The direct answer is A. Bhabar and Terai form a sequence along the Himalayan foothills, but their water conditions differ because of soil and surface materials. Bhabar contains coarse pebbles and porous deposits. Streams descending from the mountains often disappear underground there, so water sinks below the surface. Farther south, in the Terai, the deposits are finer and less porous; the underground water rises or remains close to the surface, producing wet, marshy conditions. Option A correctly states both parts of the change. Option B is wrong because these foothill belts contain freshwater streams and groundwater, not only sea water. Option C is wrong because mangroves belong mainly to saline tidal coasts and corals are marine formations; neither describes the Bhabar–Terai transition. Option D is wrong because the Terai is notably wet and marshy, not a completely dry desert, and Bhabar is not one either. Exam cue: porous Bhabar makes streams disappear; wet Terai brings water near the surface.

A shallow water table increases moisture and creates marshy conditions in Terai. For exams treat Terai as a moist foothill belt.

In flat plains rivers slow down and form meanders and floodplains. For exams remember the link between plains and river forms.

Bhangar and Khadar are two important alluvial surfaces of the northern plains. Bhangar is the older alluvium. It lies on relatively higher ground and is generally beyond the reach of ordinary annual floods. Khadar is the newer alluvium deposited in the lower floodplain by rivers during more recent floods. Because it is renewed more frequently, Khadar is often more fertile, though it can also face flooding. Therefore, option D gives the correct difference. Option A reverses both names and their relative positions, so it is incorrect. The other options describe unrelated landforms.

The easiest way to remember the distinction is old and high for Bhangar, and new and low for Khadar. River deposition is active in Khadar, while Bhangar represents an older terrace-like surface. This is a topographic as well as a geological difference: elevation and age change together in the usual textbook description. Neither unit is a coral island or a Deccan lava region. Thus option D is the only choice that correctly matches both the name and the characteristics.

A doab is alluvial land between two rivers and is useful for agriculture. For exams remember Ganga Yamuna Doab.

Brahmaputra brings high water and silt which can form floods and river islands. For exams remember Assam Valley.

Silt deposition in a delta divides the river into many distributaries. For exams remember deposition and distributary.

Sundarbans is a mangrove region developed in a tidal saline marshy delta. For exams remember the tide and mangrove link.

The Peninsular Plateau is a stable block made of old igneous and metamorphic rocks. For exams treat it as ancient India.

Many Central Highland rivers flow north and east into the Ganga Yamuna system. For exams remember Chambal Betwa Ken.

Due to the eastward slope of Deccan Plateau rivers like Godavari Krishna and Kaveri flow east. For exams study slope and river direction together.

Layered basaltic lava forms the step like landform of Deccan Trap. For exams link the word trap with steps.

Black soil swells with moisture and shrinks on drying. For exams remember black soil cotton and Deccan together.

Ancient rocky plateaus often contain abundant mineral resources. For exams link Chotanagpur with coal and iron ore.

Meghalaya Plateau is a northeastern extension of Peninsular Plateau but appears separated by plains. For exams remember Garo Khasi Jaintia.

Aravalli is an ancient mountain range eroded over a long geological time. For exams remember Aravalli as older than Himalaya.

Moist monsoon winds strike the Ghats rise upward and give rainfall. For exams remember orographic rainfall.

Mahanadi Godavari Krishna and Kaveri cut across Eastern Ghats. For exams remember Eastern Ghats as fragmented.

Nilgiri Hills are located in the contact zone of Western and Eastern Ghats. For exams remember the mountain system of South India.

Anamudi is a high peak of Western Ghats and Guru Shikhar is a peak of Aravalli. For exams do not mix mountain ranges.

Eastern Himalaya bends southward in Northeast India to form Purvanchal. For exams remember Patkai Naga Mizo.