Final answer:
The HTML web development trifecta consists of HTML5, CSS, and JavaScript, which are crucial for structuring, styling, and adding interactivity to websites.
Step-by-step explanation:
The HTML web development trifecta, essential for creating effective and interactive websites, consists of HTML5, CSS, and JavaScript. This combination allows developers to structure content with HTML5, style it with CSS, and make it interactive with JavaScript, providing a seamless user experience. Notably, Tim Berners-Lee, the inventor of the World Wide Web, developed HTML, the foundational technology that has since evolved into HTML5. On top of his innovation, community contributions have added CSS for styling and JavaScript for added front-end functionality.
The correct answer to the question is: a) HTML5, CSS, and JavaScript. These three core technologies are pivotal for web development and allow for the creation of multimodal texts that may combine images, words, sound, and animation, as per Figure 18.3.