The Chachai waterfall, formed where a stream drops over the Vindhyan scarp, is in which district of Madhya Pradesh?

The correct answer is A, Dhupgarh. Dhupgarh rises to 1,350 metres at Pachmarhi, in Narmadapuram district, and is the highest point both of the Satpura range and of Madhya Pradesh. It stands in the Mahadeo hills, the block of the Satpura that also carries the state's only hill station, and the sunset point there is the standard tourist description that papers borrow.

Option B, Amarkantak, is the plateau at the eastern end of the Satpura where the Narmada, the Son and the Johila rise; it is high ground but lower than Dhupgarh, and it is the most tempting wrong answer because it is so often named in river questions. Option C, Chauragarh, is a peak in the same Mahadeo hills near Pachmarhi, famous for its Shiva shrine, and is second to Dhupgarh. Option D, Janapav, is a hill near Mhow in Indore district on the Malwa Plateau, remembered as the source of the Chambal, not for its height.

The correct answer is B, the Amarkantak plateau. Amarkantak lies at the eastern end of the Satpura, where that range, the Maikal hills and the Vindhya come together, and three rivers begin there: the Narmada, which turns west along the rift valley, the Son, which runs east towards the Ganga, and the Johila, a tributary of the Son. One plateau sending rivers to two different seas is exactly the kind of fact examiners like.

Option A, Janapav hill near Mhow in Indore district, is the source of the Chambal, a Malwa river that flows north to the Yamuna. Option C, Multai in Betul district, is the source of the Tapti, which flows west to the Arabian Sea along a trough south of the Satpura. Option D, Pachmarhi, is the hill station in the Mahadeo hills with Dhupgarh above it, and the Tawa, the largest tributary of the Narmada, drains that area but does not rise at the same spot. Learn the four sources as a set: Amarkantak, Janapav, Multai and the Tawa country.

The correct answer is C, the basalt of the Deccan trap. Malwa was covered by the great lava flows that spread over western and central India, and the basalt they left weathers into the deep black cotton soil, locally called regur, which makes Malwa a wheat, gram, cotton and soyabean region. The flat, step-like surface of the plateau and its average height of about 500 metres are both products of the same lava sheets.

Option A, granite and gneiss, is the rock of the Bundelkhand plateau in the north, which is why that region is rocky, broken and infertile by comparison. Option B, Vindhyan sandstone, builds the Rewa and Panna country and the scarps of the Vindhya, and supplies building stone and the diamond-bearing ground of Panna. Option D, alluvium, occurs in the Narmada-Son rift and in the northern river valleys, but not on the Malwa tableland. Pair each division with its rock before the exam, because match-the-following questions use these four together.

The correct answer is A, Janapav hill near Mhow in Indore district. The Chambal begins on the Malwa Plateau at Janapav, flows north through Madhya Pradesh into Rajasthan and finally joins the Yamuna, which is why it belongs to the Ganga drainage although it starts in central India. On its way through Bhind, Morena and Sheopur it has cut the deep gullies known as the Chambal ravines, and the National Chambal Sanctuary on the river protects the gharial.

Option B, Dhupgarh at Pachmarhi, is the highest peak of the state in the Satpura and is not a river source of note. Option C, Amarkantak, gives rise to the Narmada, the Son and the Johila, and is the usual distractor in any source question about Madhya Pradesh. Option D, Multai in Betul district, is the source of the Tapti. Remember also that the Chambal's own tributaries, the Kali Sindh, the Parbati and the Shipra, are Malwa rivers that flow north for the same reason: the plateau slopes that way.

The correct answer is B, the Vindhya. The Vindhya Range runs west to east along the northern edge of the Narmada valley, and the rivers that rise on its northern slope, the Chambal, the Betwa, the Ken and the Tons, go to the Yamuna and the Ganga, while those on its southern slope go to the Narmada. That makes it the water divide between the two basins, and in tradition the line between northern and southern India.

Option A, the Satpura, lies south of the Narmada and separates the Narmada basin from the Tapti basin, which is the distinction the question is testing. Option C, the Maikal range, links the Satpura with the eastern hills and separates the Narmada headwaters from the Mahanadi and Wainganga country, a local divide rather than the great one. Option D, the Aravalli, lies in Rajasthan and is the divide between the Chambal and the Luni drainage. The Vindhya is also worth remembering as a scarp, not a folded mountain chain.