Who among the following leaders did NOT participate in the Second Round Table Conference?

Who among the following had not participated in the Second Round Table Conference?

The Indian National Congress did not take part in which of the following Round Table Conferences?

Which of the following Indian leaders attended the First Round Table Conference in London?

Mahatma Gandhi, when visited London to participate in the Second Round Table Conference, stayed at:

Which one of the following is not true about the First Round Table Conference?