Final answer:
a. all nodes have smaller values than the given node. The left subtree of a node in a binary search tree (BST) contains nodes with smaller values than the given node.
Step-by-step explanation:
The correct answer is option a. all nodes have smaller values than the given node. In a binary search tree (BST), the left subtree of a node contains all nodes with smaller values than the given node. This property allows us to efficiently search for values in a BST by navigating left or right based on whether the value we are looking for is smaller or larger than the current node.
For example, consider a BST with the following structure:
5
/ \
3 8
/ \ \
2 4 9
In this BST, the left subtree of the node 5 contains the nodes with values 3, 2, and 4, all of which have smaller values than 5.