var textToFind = 'Google';

var dd = document.getElementById('MyDropDown');
for (var i = 0; i < dd.options.length; i++) {
    if (dd.options[i].text === textToFind) {
        dd.selectedIndex = i;
        break;
    }
}

 

HTML SELECT - Change selected option by VALUE using JavaScript

You can select the value using javascript:

document.getElementById('sel').value = 'bike';