Merge branch 'MDL-72669-311' of git://github.com/rezaies/moodle into …

…MOODLE_311_STABLE

question/type/multianswer/renderer.php

@@ -299,7 +299,7 @@ public function subquestion(question_attempt $qa, question_display_options $opti
             $feedbackimg = $this->feedback_image($matchinganswer->fraction);
         }
         $select = html_writer::select($choices, $qa->get_qt_field_name($fieldname),
-                $response, array('' => ''), $inputattributes);
+                $response, array('' => ' '), $inputattributes);
 
         $order = $subq->get_order($qa);
         $correctresponses = $subq->get_correct_response();