How can the JavaScript part of the code be modified to trigger the AJAX request based on a selection from a dropdown menu rather than clicking a button?

To trigger an AJAX request based on a selection from a dropdown menu, you can use the "change" event listener on the dropdown menu. This event will be triggered whenever the selected option in the dropdown menu is changed. Inside the event listener function, you can make the AJAX request to fetch data based on the selected option. ```javascript document.getElementById('dropdown').addEventListener('change', function() { var selectedOption = this.value; // Make AJAX request here using selectedOption // Example AJAX request code: // var xhr = new XMLHttpRequest(); // xhr.open('GET', 'ajax_data.php?option=' + selectedOption, true); // xhr.onload = function() { // if (xhr.status >= 200 && xhr.status < 300) { // console.log(xhr.responseText); // } else { // console.error('Request failed'); // } // }; // xhr.send(); }); ```