Option 1 states that the National Anthem of India was adopted by the Constituent Assembly on 24th January, 1950. This statement is correct. The National Anthem of India, "Jana Gana Mana," was officially adopted as the national anthem of India on 24th January 1950. The song was written by Rabindranath Tagore and was chosen to represent the unity and diversity of the country.

Option 2 states that the first political occasion when the National Song of India was sung was the 1896 Session of the Indian National Congress. This statement is also correct. The National Song of India, "Vande Mataram," was sung for the first time at the 1896 session of the Indian National Congress. It was written by Bankim Chandra Chatterjee and became a rallying cry for the Indian freedom movement.

Both statements are correct, so the correct answer is option 3, "Both 1 and 2." The National Anthem and the National Song of India have significant cultural and historical importance in India and are symbols of patriotism and national unity.