The correct answer is: Both 1 and 2.
The final breaking up of the old Gondwana continent happened in the Mesozoic era, not the Tertiary period. The upheaval of the Himalayas altered the old topography of the subcontinent in the Tertiary period.
The Tertiary period is the second of the three periods of the Cenozoic era, lasting from 66 million years ago to 2.6 million years ago. It is subdivided into the Paleogene and Neogene epochs. The Tertiary period is characterized by the rise of mammals and the decline of dinosaurs.
The Mesozoic era is the middle of the three eras of the Phanerozoic eon, lasting from 252 to 66 million years ago. It is subdivided into the Triassic, Jurassic, and Cretaceous periods. The Mesozoic era is characterized by the rise of dinosaurs and the decline of amphibians.
The Himalayas are a mountain range in Asia that separates the Indian subcontinent from the Tibetan Plateau. The Himalayas are the highest mountain range in the world, and they are home to Mount Everest, the highest mountain on Earth. The Himalayas were formed by the collision of the Indian and Eurasian tectonic plates.
The upheaval of the Himalayas altered the old topography of the subcontinent by raising the land and creating a series of mountain ranges. The Himalayas also caused the climate of the subcontinent to change, making it cooler and drier.