資料結構與演算法

(5 points)（單選）We now use several algorithms to traverse a binary tree. Assuming there are a total number of $N$ nodes, how many of the following statements about the worst-case space complexity are TRUE?

• Using DFS to traverse a balanced binary tree takes $O(N)$.
• Using DFS to traverse a binary tree takes $O(N)$.
• Using BFS to traverse a balanced binary tree takes $O(N)$.
• Using BFS to traverse a binary tree takes $O(N)$.