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<!DOCTYPE html> <html> <body> <select id="mySelect"> <option>Apple</option> <option>Pear</option> <option>Banana</option> <option>Orange</option> </select> <p>Click the button to return the number of option elements in the dropdown list.</p> <button onclick="myFunction()">Try it</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("mySelect").length; document.getElementById("demo").innerHTML = x; } </script> </body> </html>