The correct answer is C. Priority Queue.
A priority queue is a data structure that stores
elements in a sorted order, with the highest-priority element at the front of the queue. This makes it a natural choice for implementing best-first search, which is a search algorithm that always expands the node with the highest estimated cost to goal.A queue is a data structure that stores elements in a first-in, first-out (FIFO) order. This means that the element that was added to the queue first will be the first element to be removed. A stack is a data structure that stores elements in a last-in, first-out (LIFO) order. This means that the element that was added to the stack last will be the first element to be removed. A circular queue is a data structure that stores elements in a circular buffer. This means that the elements are stored in a ring, and the last element in the buffer is connected to the first element.
Best-first search can be implemented using a queue, a stack, or a priority queue. However, a priority queue is the most efficient data structure for implementing best-first search, because it allows the algorithm to quickly access the node with the highest estimated cost to goal.