Code that executes when the user clicks a button at runtime is known as __________.

What are the four primary components of a public key infrastructure implementation?

A. Confidentiality, Integrity, Availability, and Non-repudiation B. Public key encryption, split-key encryption, initialization vectors, biometrics C. Symmetric encryption, asymmetric encryption, hashing, and digital certificates D. Authentication, Authorization, Accounting, and Availability

What is the correct code for void add(String x) operation? Such an operation adds x to the queue

A queue based on a linked list uses the following code ``` class Node { String element; Node next; Node (String el, Node n) { element = el; next = n; } } Node front = null, rear = null; ``` A) rear = new Node(x, null); B) rear = new Node(x, null); rear = rear.next; C) if (rear != null) { rear.next = new Node(x, null); rear = rear.next; } else { rear = new Node(x, null); front = rear; } D) if (rear != null) { rear.next = new Node(x, null); rear = rear.next; } else { rear.next = new Node(x, null); front = rear; }