Answer:
Congress was formed by Allan Octavian Hume at Bombay as an entertainment club (as written in its then preamble) in 1885. British had decided to enroll educated Indian people in this party and use it as a safety valve against the growing freedom struggle.
If Mahatma Gandhi would not have come to India from South Africa, then there would have been no one even talking of Congress. It was Mahatma Gandhi who gave life to Congress. Till then, no one even knew that there was something called Congress!
Gandhiji made Congress as a means of freedom struggle. But unfortunately, things did not go well. Later on, Gandhiji became so sad and unhappy with Congress that he resigned from the party for lifetime. He did not even take the membership of the Congress party.
This is an unknown bitter truth hidden which is lost in history (perhaps, wiped from history) :
During his last days, Gandhiji had said that 'Destroy Congress completely...if Congress doesn't get destroyed, it will loot India the same way British looted this country'
But the Congressmen did not destroy Congress, instead destroyed Gandhiji because Gandhiji had become an obstacle for Congress.