Which one of the following statements is not correct regarding the Himalayas ?

Statement 3 is incorrect because the Kunlun Ranges are not part of the Himalayas; they are a separate mountain system in Central Asia that bounds the Tibetan Plateau to the north [t6][t8]. The Himalayas primarily consist of three parallel longitudinal ranges: the Great Himalayas (Himadri), the Lesser Himalayas (Himachal), and the Outer Himalayas (Siwaliks) [c1][t2]. Regarding the other options: the Himalayas formed from the sediments of the Tethys Sea (geosyncline) due to the collision of the Indian and Eurasian plates [c1][c3][c4]. This orogeny occurred during the Tertiary Era, with major upheavals spanning from the Eocene to the Pliocene/Post-Pliocene periods [c1][c5]. Structurally, the Himalayas are characterized by complex tectonic features, including large-scale nappe structures and recumbent folds, particularly where the Higher Himalayan Crystallines are thrust over the Lesser Himalayas [t1].

Sources

1. [1] https://portals.iucn.org/library/sites/library/files/documents/PAPS-006.pdf
2. [2] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 2: Physiography > i) The Geosynclinal Origin > p. 3
3. [3] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 2: Physiography > ii) The Plate Tectonic Origin of the Himalaya > p. 6
4. [4] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 8: Convergent Boundary > Phases of Formation > p. 122
5. [5] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 1: Geological Structure and formation of India > THE TERTIARY SYSTEM (THE CENOZOIC ERA) > p. 22
6. [6] https://www.sciencedirect.com/topics/earth-and-planetary-sciences/himalayan-orogeny