diff --git a/question/type/truefalse/renderer.php b/question/type/truefalse/renderer.php
index 9b3df0133b0..201e606e0a0 100644
--- a/question/type/truefalse/renderer.php
+++ b/question/type/truefalse/renderer.php
@@ -99,11 +99,14 @@ class qtype_truefalse_renderer extends qtype_renderer {
         $result .= html_writer::tag('div', $question->format_questiontext($qa),
                 array('class' => 'qtext'));
 
-        $result .= html_writer::start_tag('div', array('class' => 'ablock'));
+        $result .= html_writer::start_tag('fieldset', array('class' => 'ablock'));
+        $legendclass = 'sr-only';
         if (!empty($question->showstandardinstruction)) {
-            $result .= html_writer::tag('div', get_string('selectone', 'qtype_truefalse'),
-                array('class' => 'prompt'));
+            $legendclass = '';
         }
+        $questionnumber = $options->add_question_identifier_to_label(get_string('selectone', 'qtype_truefalse'), true, true);
+        $result .= html_writer::tag('legend', $questionnumber,
+            array('class' => 'prompt h6 font-weight-normal ' . $legendclass));
 
         $result .= html_writer::start_tag('div', array('class' => 'answer'));
         $result .= html_writer::tag('div', $radiotrue . ' ' . $truefeedbackimg,
@@ -112,7 +115,7 @@ class qtype_truefalse_renderer extends qtype_renderer {
                 array('class' => 'r1' . $falseclass));
         $result .= html_writer::end_tag('div'); // Answer.
 
-        $result .= html_writer::end_tag('div'); // Ablock.
+        $result .= html_writer::end_tag('fieldset'); // Ablock.
 
         if ($qa->get_state() == question_state::$invalid) {
             $result .= html_writer::nonempty_tag('div',
diff --git a/question/type/truefalse/tests/walkthrough_test.php b/question/type/truefalse/tests/walkthrough_test.php
index cbae25ee7d2..07721a69fe0 100644
--- a/question/type/truefalse/tests/walkthrough_test.php
+++ b/question/type/truefalse/tests/walkthrough_test.php
@@ -155,7 +155,9 @@ class walkthrough_test extends \qbehaviour_walkthrough_test_base {
         $this->render();
 
         // Check for 'Show standard instruction'.
-        $standardinstruction = get_string('selectone', 'qtype_truefalse');
-        $this->assertStringNotContainsString($standardinstruction, $this->currentoutput);
+        $standardinstruction = \html_writer::tag('legend', get_string('selectone', 'qtype_truefalse'), [
+            'class' => 'prompt h6 font-weight-normal sr-only'
+        ]);
+        $this->assertStringContainsString($standardinstruction, $this->currentoutput);
     }
 }