Explanation:

- Abdicate (Option 2): To give up or renounce the throne or position of authority, especially in a formal or voluntary way. This is the correct option.

- Usurp (Option 1): To take a position of power or importance illegally or by force, not by giving it up.

- Consign (Option 3): To deliver something to a person's custody, typically in order to be sold. Not related to giving up a throne.

- Bequeath (Option 4): To leave personal estate or one's body to a person or other beneficiary by a will. It involves passing something on rather than giving up power or position.