Explanation:

- The occupational structure of India is divided into different sectors, which are crucial for understanding the economy.

- Option 1: One

- This is incorrect. The Indian occupational structure is more nuanced than a single sector.

- Option 2: Two

- Also not accurate. While economies may have primary and secondary sectors, India's structure includes more detail.

- Option 3: Three

- Primary Sector: Involves natural resource extraction, like farming, mining, and fishing.

- Secondary Sector: Includes manufacturing and industry activities.

- Tertiary Sector: Covers services like education, healthcare, banking, etc.

- This option correctly captures the typical division of occupations in India.

- Option 4: Four

- There is sometimes debate around a quaternary sector focusing on information and knowledge, but traditionally, India recognizes three main sectors.