var text1 = 'Two';_x000D_
$("select option").filter(function() {_x000D_
//may want to use $.trim in here_x000D_
return $(this).text() == text1;_x000D_
}).prop('selected', true);
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
_x000D_
<select>_x000D_
<option value="0">One</option>_x000D_
<option value="1">Two</option>_x000D_
</select>
_x000D_
var text1 = 'Two';_x000D_
$("select option").filter(function() {_x000D_
//may want to use $.trim in here_x000D_
return $(this).text() == text1;_x000D_
}).attr('selected', true);
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.4.0/jquery.min.js"></script>_x000D_
_x000D_
<select>_x000D_
<option value="0">One</option>_x000D_
<option value="1">Two</option>_x000D_
</select>
_x000D_
Note that while this approach will work in versions that are above 1.6 but less than 1.9, it has been deprecated since 1.6. It will not work in jQuery 1.9+.
val()
should handle both cases.
$('select').val('1'); // selects "Two"_x000D_
$('select').val('Two'); // also selects "Two"
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.2.3/jquery.min.js"></script>_x000D_
_x000D_
<select>_x000D_
<option value="0">One</option>_x000D_
<option value="1">Two</option>_x000D_
</select>
_x000D_