Answer:
The correct answer is A. Speaker of the House.
Step-by-step explanation:
The Speaker is considered as the person in charge of the House of Representatives in terms of politics. The Speaker also must manage the different administrative aspects of the House of Representatives.
When a new Congress is emerging, the Speaker is elected by most of the Representatives and the Speaker can succeed the President when the Vice President cannot fulfill its functions. Thus, the 25th Amendment establishes that the Speaker cannot be in the process of being President.