Guwahati High Court is the judicature of

Assam
Nagaland
Arunachal Pradesh
All of the above

The correct answer is D. All of the above.

The Guwahati High Court is the highest court of law in the Indian state of Assam and the northeastern states of Arunachal Pradesh, Nagaland, Manipur, Mizoram, Meghalaya, and Tripura. It was established on 1 January 1948, and its headquarters are located in Guwahati, Assam.

The Guwahati High Court has original jurisdiction in civil and criminal matters, and it also has appellate jurisdiction over the decisions of lower courts in the states under its jurisdiction. The High Court is headed by a Chief Justice, and there are a number of other judges who are appointed by the President of India.

The Guwahati High Court is a very important institution in the northeastern region of India. It plays a vital role in upholding the rule of law and ensuring justice for all.