The correct answer is: b) The Constitution of India.
The Constitution of India guarantees freedom of the press in Article 19(1)(a). This article states that all citizens have the right to freedom of speech and expression, which includes the freedom of the press.
The Arunachal Pradesh Press Act is a state law that regulates the printing and publication of newspapers and other periodicals in Arunachal Pradesh. The Act does not contain any provisions that specifically guarantee freedom of the press.
Tribal customary laws are the traditional laws and customs of the tribal people of Arunachal Pradesh. These laws are not codified and are not enforceable in a court of law. They do not contain any provisions that specifically guarantee freedom of the press.
International treaties are agreements between countries. The Indian government has signed a number of international treaties that guarantee freedom of the press. However, these treaties are not directly enforceable in Indian courts.
Therefore, the correct answer is: b) The Constitution of India.