Explanation:

Both statements are incorrect.

• The Prime Minister paid tributes to Mahatma Gandhi and all the eminent persons who marched to Dandi in order to protest injustice and protect our nation's self-esteem.
• The Dandi March was an act of nonviolent civil disobedience led by Mohandas Karamchand Gandhi.
• The march lasted from 12th March 1930 to 6th April 1930 as a direct action campaign of tax resistance and nonviolent protest against the British salt monopoly. 
• At Dandi, thousands more followed his lead, and in the coastal cities of Bombay and Karachi, Indian nationalists led crowds of citizens in making salt.
• The Viceroy of India at the time of Dandi March was Lord Irwin.

Hence option 4th is correct.