Explanation:

All the statements are correct.
Jayaprakash Narayan (11 October 1902 – 8 October 1979), popularly referred to as JP or Lok Nayak, was an Indian independence activist, theorist and political leader, remembered especially for leading the mid-1970s opposition against Prime Minister Indira Gandhi, for whose overthrow he called a "total revolution".
First statement is correct because he was the General Secretary of Congress Socialist Party.
Second statement is correct. When Mahatma Gandhi launched the Quit India Movement in August 1942, Yogendra Shukla scaled the wall of Hazaribagh Central Jail along with Jayaprakash Narayan, Suraj Narayan Singh, Gulab Chand Gupta, Pandit Ramnandan Mishra, Shaligram Singh and Shyam Barthwar, with a goal to start an underground movement for freedom.
Third statement is also correct. JP Narayan withdrew from active politics to join Bhoodan movement in 1950s.