What is the order of nodes processed in a preorder tree traversal?

In a preorder tree traversal, the order of processing nodes is to visit the parent node first and then process its children. This means for each node, you record or print the value of the node itself before moving on to its children.

The steps followed in a preorder traversal are:

1. Visit the current node (parent).

2. Recursively perform a preorder traversal on the left subtree.

3. Recursively perform a preorder traversal on the right subtree.

This method is particularly useful in applications where you need to create a copy of a tree or assess a tree structure from top to bottom, preserving the hierarchical relationships.

The mention of children being processed before the parent or in any alternate order is not characteristic of preorder traversal, which distinctly prioritizes the parent node. This distinction helps clarify why the correct answer focuses on performing actions centered around the parent before addressing its children directly.