Which one of the following languages was recognised as the official language of Sri Lanka in 1956 ?
A) English
B) Tamil
C) Urdu
D) Sinhala

Hint:
The main issue affecting India-Sri Lanka relations in 1982 to 2001 is the Tamil minority community of Sri Lanka. Of Sri Lanka's population of 21.2 million, 74 percent are Sinhalese, 13 percent Sri Lankan Tamil, 6 percent Indian-origin Tamil and the remaining others. Tamils ​​live in Jaffna district in the north of Sri Lanka. Tamil people are religiously called Hindus and Sinhalese Buddhists. Insecurity among Sri Lankan Tamils ​​for several reasons.

Complete step by step solution:
The root cause of the present-day movement of Sri Lankan Tamils ​​is the policy of discrimination by the majority Sinhalese. On one hand the Sinhalese ruling class has a monopoly in the economic, social and political spheres of the country and on the other hand Buddhism has been made the national religion of the country and the Sinhalese language has been given the status of the national language.

Tamils were some some issues -
1) They are discriminated against while recruiting in government jobs and entering universities.
2) The government is deliberately settling Sinhalese farmers in Tamil areas so that Tamil people become a minority in the home itself.
3) To break the power of the organization of Tamils, the government is forcibly spreading Tamil minorities to other parts of the country.
4) Jayawardene government is spreading government terrorism on the pretext of eliminating the militants.

So, option D is the correct answer.

Note:
The Sri Lankan Tamil community has organized itself (TULF) into a political organization called 'Tamil United Liberation Front' and through this it also expresses its displeasure from time to time. Some militant organizations of Tamils ​​talk of the creation of a separate nation called Ealam (Elam-Ealam) but the main organization of Tamils' Tulf (TULF) demands autonomy only. This organization does not want to divide Sri Lanka but it wants to have a dignified life for the Tamils ​​like the citizens of an independent country. This issue is the root of the Tamil movement.