Explanation:

- The first Industrial Policy in India, based on the mixed economy principle, was announced in 1948.

- This policy outlined the distinct roles for both public and private sectors.

- Option 2: 1948 - The right answer. It marked the beginning of structured industrial growth in post-independence India.

- Option 1: 1959, does not relate to the first Industrial Policy.

- Option 3: 1950, while significant for the Indian economy, does not mark the introduction of the first Industrial Policy.

- Option 4: 1962, also not relevant to the first Industrial Policy announcement.