/**
* Like {@link render_question()} but displays the question at the past step
* indicated by $seq, rather than showing the latest step.
*
* @param int $seq the seq number of the past state to display.
* @param question_display_options $options controls how the question is rendered.
* @param string|null $number The question number to display. 'i' is a special
* value that gets displayed as Information. Null means no number is displayed.
* @return string HTML fragment representing the question.
*/
public function render_at_step($seq, $options, $number, $preferredbehaviour)
{
$restrictedqa = new question_attempt_with_restricted_history($this, $seq, $preferredbehaviour);
return $restrictedqa->render($options, $number);
}
