Explanation:

The 31st Session of the Congress was held at Lucknow in 1916. It was presided over by the Ambica Charan Majumdar who was a prominent lawyer and was actively associated with the Congress since its birth, finally readmitted the Extremists led by Tilak to the Congress fold.
After a lapse of about 10 years both the Moderates and Extremists were united again which was a good sign for the national movement. In his address the President declared 'If the United Congress was buried at Surat it is reborn at Lucknow in the garden of Wajid Ali Shah. After nearly 10 years of painful separation and wanderings through the wilderness of misunderstandings the brother had at first met brothers'. In this session the Congress and the Muslim League came closer to each other and they signed the historic Lucknow Pact.
While the League agreed to present joint constitutional demands with the Congress to the Government, the Congress accepted the Muslim League's position on separate electorates.
Bal Gangadhar Tilak was a leader of extremists.
Do you know?
•Despite being a controversial decision (Lucknow Pact), the acceptance of the principle of separate electorates represented a serious desire to allay minority fears of majority domination.
•There was a large amount of enthusiasm generated among the people by this reunion. Even the Government decided to placate the nationalists by declaring its intention to grant self-government to Indians, as contained in Montagu's August 1917 declaration.
THINK!
•'carrot and stick' policy of British Indian government after First World War.