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<!DOCTYPE html> <html> <body> <select id="mySelect"> <option>Cat</option> <option>Dog</option> <option>Horse</option> </select> <p>Click the button to find out if more than one option in the dropdown list can be selected.</p> <button onclick="myFunction()">Try it</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("mySelect").multiple; document.getElementById("demo").innerHTML = x; } </script> </body> </html>