Physiographic Divisions — Set 3

Correct Answer: A. Coral accumulation

• **Lakshadweep** = a group of coral atolls formed by coral reef accumulation in the Arabian Sea, west of Kerala. • **36 islands** — total number; only 10 are inhabited; Lakshadweep means 'a hundred thousand islands'. • 💡 Wrong-option analysis: River sedimentation: forms deltas and alluvial plains, not atolls; Volcanic activity: forms volcanic islands like Barren and Narcondam; Folding of crust: forms fold mountains like the Himalayas.

Correct Answer: C. Ten Degree Channel

• **Ten Degree Channel** = a maritime boundary at 10 deg N latitude separating the Andaman group (north) from the Nicobar group (south). • **~150 km wide** — width of the Ten Degree Channel, a strategically important waterway. • 💡 Wrong-option analysis: Palk Strait: separates India (Tamil Nadu) from Sri Lanka; Gulf of Mannar: water body between India and Sri Lanka south of Palk Strait; Nine Degree Channel: separates Lakshadweep's Minicoy Island from the main island group.

Correct Answer: A. Barren Island

• **Barren Island** = home to India's only confirmed active volcano, located in the Andaman Sea. • **First erupted 1787** — recorded history; last significant eruption was in 2017; dormant between 1832 and 1991. • 💡 Wrong-option analysis: Laccadive Islands: coral islands (Lakshadweep), not volcanic; Narcondam Island: an extinct volcano in Andaman Sea, not active; Minicoy Island: part of Lakshadweep, a coral atoll.

Correct Answer: B. Saddle Peak

• **Saddle Peak** = highest point of the Andaman and Nicobar archipelago at 732 m, located in North Andaman. • **732 m** — elevation of Saddle Peak; surrounded by Saddle Peak National Park. • 💡 Wrong-option analysis: Mount Diavolo: in South Andaman, lower than Saddle Peak; Mount Thullier: highest peak of Great Nicobar Island at 642 m, not the overall highest; Mount Harriet: in South Andaman at 365 m.

Correct Answer: B. Basalt

• **Basalt** = the primary rock type of the Deccan Trap, formed by solidification of ancient volcanic lava flows. • **500,000 sq km** — area covered by Deccan Trap lavas; weathering of basalt formed the fertile black (Regur) soil. • 💡 Wrong-option analysis: Marble: metamorphic rock found in Rajasthan, not the Deccan Trap; Granite: igneous rock common in Peninsular India but not the Deccan lava region; Sandstone: sedimentary rock of the Vindhyan formation.

Correct Answer: D. Thar Desert

• **Thar Desert** = also called the Great Indian Desert, located mostly in Rajasthan; arid region with low rainfall and high evaporation. • **Luni river** — the only significant river flowing through the Thar Desert, ending in the Rann of Kutch. • 💡 Wrong-option analysis: Ladakh Desert: a cold high-altitude desert, not the Great Desert; Spiti Valley: cold arid valley in Himachal Pradesh, not called Great Desert; Rann of Kutch: seasonal salt marsh in Gujarat, not a desert.

Correct Answer: D. Peninsular Plateau

• **Peninsular Plateau** = geologically the oldest physiographic division, formed from the ancient Gondwanaland landmass. • **Precambrian age** — composed of old crystalline, igneous, and metamorphic rocks; a stable, rigid crustal block unlike the Himalayas. • 💡 Wrong-option analysis: Himalayan Mountains: geologically youngest, formed only ~50 million years ago by collision of Indian and Eurasian plates; Northern Plains: alluvial plains formed by Himalayan rivers, recent in geological age; Coastal Plains: formed by marine deposition and river deltas, also relatively recent.

Correct Answer: A. South-Western

• **Malabar Coast** = the southern section of the Western Coastal Plain, mainly covering Kerala's coastline. • **Kayals (backwaters)** — the famous network of lagoons, canals, and rivers that make Malabar Coast unique. • 💡 Wrong-option analysis: North-Eastern: that region has no significant western coastal plain; South-Eastern: that is the Coromandel Coast along the Bay of Bengal; North-Western: Gujarat coastline, not called Malabar.

Correct Answer: B. Punjab

• **Punjab** = the Indian state that does NOT share a boundary with the Himalayas; it lies in the plains at the foothills. • **Five rivers** — Punjab is characterized by the fertile plains of five rivers: Jhelum, Chenab, Ravi, Beas, and Satluj. • 💡 Wrong-option analysis: Sikkim: entirely within the Himalayan belt, bordered by Nepal, Bhutan, and China; Uttarakhand: large portion lies within the Himalayan mountains; Arunachal Pradesh: easternmost state bordered by the Himalayas and China.

Correct Answer: D. Two rivers

• **Doab** = fertile land lying between two rivers, derived from Persian words 'do' (two) and 'ab' (water). • **Ganga-Yamuna Doab** — the most prominent Doab in India, one of the most densely populated agricultural regions. • 💡 Wrong-option analysis: Land and Sea: that describes a peninsula or cape, not a Doab; Two mountains: the land between mountains is called a valley or dun; Mountain and Plain: that is a transitional zone, not a Doab.