'mod_quiz_get_attempt_review' => array(
'classname' => 'mod_quiz_external',
'methodname' => 'get_attempt_review',
'description' => 'Returns review information for the given finished attempt, can be used by users or teachers.',
'type' => 'read',
'capabilities' => 'mod/quiz:reviewmyattempts',
'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE)
),
https://github.com/moodle/moodle/blob/master/mod/quiz/classes/external.php#L1384
https://github.com/moodle/moodle/blob/master/mod/quiz/classes/external.php#L865 shows that the return value includes question data.