The correct answer is 2 only.

• Notification, on OCI card-holders published in March 2021 has provided the following provisions:
  • Grant of a multiple-entry life-long visa for visiting India for any purpose.
  • Special permission is required to:
    • undertake any research; 
    • undertake any missionary or mountaineering or journalistic activities;
    • undertake internships in any foreign diplomatic missions; and 
    • visit any place that falls within the so-called protected or restricted or prohibited areas.
    • Hence, statement 3 is incorrect.
  • Purchase or sale of immovable properties other than agricultural land or farmhouse or plantation property. Hence, statement 1 is incorrect.
  • Pursuing the following professions: doctors, dentists, nurses, and pharmacists, advocates, architects, and chartered accountants.
    • Hence, statement 2 is correct.

 Other provisions:

• Exemption from registration with the Foreigners Regional Registration Officer for any length of stay in India. 
• OCI card-holders will enjoy parity with Indian nationals in the matters of tariffs in airfares in domestic sectors in India, and entry fees to be charged for visiting sites.
• The concept of OCI was brought through the Citizenship Act, 1955.
• The government of India launched the Overseas Citizenship of India Scheme in 2005.
• On 9 January 2015, the GOI merged the Persons of Indian Origin card scheme with the OCI card scheme.
• Provisions related to Indian Citizenship are mentioned in Article 5-11, Part - II^nd of the Indian Constitution.