A binary search tree is a data structure for maintaining sets of values like integers, which can be compared using a <= relation. A binary search tree is either empty, or it consists of a node with two binary search trees as subtrees. Each node holds an integer element. Binary search trees satisfy the following invariant:The elements held in the left subtree of a node are smaller than the element n at the node, and the elements held in the right subtree of the node are larger than n. a. Describe an implementation of binary search trees in terms of records and pointers. b. Write a function member to determine if an integer is held at some node in a binary search tree. c. Write a function print that prints the elements within a binary search tree in increasing order.