The correct answer is: A. Stacks
A depth-first search (DFS) is an algorithm for traversing a graph. It starts at a given node and explores all of the node’s neighbors before moving on to any other nodes. This process is repeated until all of the nodes in the graph have been visited.
A stack is a data structure that stores data in a last-in, first-out (LIFO) order. This means that the last item added to the stack is the first item to be removed. This makes stacks a natural choice for implementing DFS, as the algorithm can simply add each node to the stack as it is visited and then remove the nodes from the stack in the order in which they were added.
Queues are also a data structure that stores data in a LIFO order, but they are not as well-suited for implementing DFS as stacks. This is because queues are typically used to
implement algorithms that need to process data in a specific order, such as the first-in, first-out (FIFO) algorithm. DFS, on the other hand, does not need to process data in a specific order, so it can use a stack instead of a queue.Priority queues are a data structure that stores data in a sorted order. This means that the data is stored in a way that makes it easy to find the item with the highest priority. Priority queues are not well-suited for implementing DFS, as the algorithm does not need to find the item with the highest priority. Instead, it simply needs to find the next node to visit, which can be done using a stack.
Therefore, the correct answer is: A. Stacks