Explanation:

The first-ever motion to remove a Supreme Court Justice in India was signed in 1991. Here's a breakdown:

- Option 1: 1996

This year does not relate to any significant event concerning the impeachment of a Supreme Court Justice.

- Option 2: 1978

There was no motion to impeach a Supreme Court Justice in this year.

- Option 3: 1984

This year doesn’t correspond with the motion for removal of a Justice.

- Option 4: 1991

Correct Answer

In this year, 108 members of the Indian Parliament signed a motion to remove Justice V. Ramaswami.

This marks the first instance that a motion of this kind was signed in India.