The correct answer is 1 and 2 only.

• The Preamble of the Indian Constitution is based on the objective resolution drafted and moved by Jawaharlal Nehru and adopted by the constituent assembly.
• The Preamble reveals 4 ingredients of the components

1. Source of the authority of the Constitution: The Preamble states that the Constitution derives its authority from the people of India.
2. Nature of Indian State: It declares India to be of a sovereign, socialist, secular democratic, and republican polity.
3. Objectives of the Constitution: It specifies justice, liberty, equality, and fraternity as the objectives. 
4. Date of adoption of the Constitution: It stipulates November 26, 1949, as the date.

• The word socialism is added by the 42nd amendment in 1976 in the Preamble of the Indian Constitution. Hence, Statement 2 is correct.
  • The constitution has socialist nature in the form of the directive principle of State Policy (DPSP). 
  • The Congress party adopted a resolution to establish a socialist pattern of society in its Avadi session in 1955. Hence, Statement 1 is correct.
  • However, the Indian brand of socialism is democratic socialism and not communist socialism. 
  • Democratic socialism holds faith in a mixed economy where both the public and private sectors coexist side by side. 
  • Democratic socialism aims to end poverty, ignorance, disease, and inequality of opportunity. 
  • Indian socialism is a blend of Marxism and Gandhism leaning heavily towards Gandhian socialism. 
  • The new economic policy of liberalization, privatization, and globalization in 1991 however diluted the socialist credentials of the Indian state to an extent.

• The Supreme Court ruled that Preamble is not a part of the Constitution in the Berubari Union case (1960).
• In the Kesavananda Bharati v. State of Kerala (1973), the Supreme Court overruled the ruling in Berubari Union Case (1960) and held that Preamble is a part of the Constitution. 
• The Preamble is neither a source of power to the legislature nor a prohibition upon the powers of legislation. 
• It is non-justiciable which means provisions are not enforceable in a court of law. Hence, Statement 3 is incorrect.