The Assam Accord of 1985 sought to address issues of:

The correct answer is: a) Illegal immigration.

The Assam Accord was a peace accord signed on 15 August 1985 between the Government of India and the All Assam Students Union (AASU). The accord was signed to end the Assam Agitation, a six-year-long movement against illegal immigration from Bangladesh into the Indian state of Assam.

The accord sought to address the issue of illegal immigration by identifying and deporting illegal immigrants, and by providing safeguards for the indigenous people of Assam. The accord also provided for economic development and language policy in Assam.

Here is a brief explanation of each option:

• Option a) Illegal immigration: The Assam Accord sought to address the issue of illegal immigration by identifying and deporting illegal immigrants, and by providing safeguards for the indigenous people of Assam.
• Option b) Economic development: The Assam Accord also provided for economic development in Assam, including the establishment of new industries and the development of infrastructure.
• Option c) Language policy: The Assam Accord also provided for language policy in Assam, including the recognition of Assamese as the official language of the state.
• Option d) Tribal autonomy: The Assam Accord did not address the issue of tribal autonomy.