Select Drop Down Does Not Work In Mobile Device When Apply Bootstrap

I'm using html select in the bootstrap col, but when i click drop down button in the mobile device(iOS and Android), it can not display the option list. But it works in the PC brow

Solution 1:

Try using like this

<formrole="form"><divclass="form-group"><divclass="col-xs-6 col-sm-6 col-md-6"><selectclass="form-control"><option>1</option><option>2</option><option>3</option><option>4</option><option>5</option></select></div><divclass="col-xs-6 col-sm-6 col-md-6"><selectclass="form-control"><option>1</option><option>2</option><option>3</option><option>4</option><option>5</option></select></div></div></form>

Working fiddle http://jsfiddle.net/52VtD/9092/