The correct answer is option 'A', The Himalayas.

Explanation:
The physiographic division of India formed out of accumulations in the Tethys geosyncline is the Himalayas.

1. Introduction to the Tethys geosyncline:
The Tethys geosyncline was a large oceanic basin that existed during the Paleozoic and Mesozoic eras. It extended from the present-day Mediterranean region to the Indian subcontinent. Over millions of years, sediments accumulated in this geosyncline, leading to the formation of various mountain ranges, including the Himalayas.

2. Formation of the Himalayas:
The Himalayas were formed as a result of the collision between the Indian Plate and the Eurasian Plate. Around 50 million years ago, the Indian Plate, which was then located south of the Equator, began moving northwards towards the Eurasian Plate. As the Indian Plate moved, it pushed against the Eurasian Plate, causing the sediments in the Tethys geosyncline to buckle and fold.

3. Thrust faulting and uplift:
The collision between the two plates resulted in intense compression and thrust faulting. Thrust faulting occurs when one rock mass is pushed over another along a nearly horizontal fault plane. This process led to the uplift of the sediments in the Tethys geosyncline, giving rise to the towering Himalayan mountain range.

4. Formation of different ranges:
The Himalayas consist of several parallel mountain ranges, each with its own distinct features. The main ranges include the Great Himalayas, Lesser Himalayas, and Outer Himalayas. The Great Himalayas, also known as the Himadri, are the highest and most continuous range, with peaks reaching over 8,000 meters, including Mount Everest.

5. Impact on the Indian subcontinent:
The formation of the Himalayas has had a significant impact on the Indian subcontinent. The mountain range acts as a barrier, preventing the cold winds from Central Asia from reaching the Indian plains, resulting in a diverse range of climates within the country. The Himalayas also play a crucial role in the Indian monsoon system, as they block the moisture-laden winds from the Indian Ocean, leading to heavy rainfall in the northern region.

In conclusion, the Himalayas were formed as a result of the collision between the Indian Plate and the Eurasian Plate, which caused the uplift of sediments in the Tethys geosyncline. This physiographic division of India is characterized by its towering peaks, diverse climatic conditions, and crucial role in the Indian monsoon system.