25.
The answer is: A
Explanation
The correct option is A: Delimitation Commission.
The Delimitation Commission is an independent body that is entrusted with the task of readjusting the boundaries and sizes of the Lok Sabha constituencies based on the latest census data.
The Delimitation Commission also determines the number of seats to be reserved for Scheduled Castes and Scheduled Tribes in each state. The Election Commission of India, the Census Commission, and the President do not have the authority to delimit the Lok Sabha constituencies.