UNION and ORDER BY RANDOM()

$end_line = "\n";
$rand = rand(1,5);
$query = "SELECT q.q_id, q.q_quest, a.a_id, a.a_answer, a.a_correct
                FROM answer a 
                RIGHT JOIN  (SELECT q_id, q_quest 
                                FROM question WHERE q_id=$rand) q USING(q_id) WHERE a.a_correct = 1
                            UNION 
        SELECT q.q_id, q.q_quest, a.a_id, a.a_answer, a.a_correct
                    FROM answer a 
                    RIGHT JOIN  (SELECT q_id, q_quest  
                                    FROM question  WHERE q_id=$rand)  q USING(q_id) WHERE a.a_correct = 0 LIMIT 4 
            ";

FROM question  WHERE q_id=$rand)  q USING(q_id) WHERE a.a_correct = 0 ORDER BY RANDOM() LIMIT 4

$rand = rand(1,2);  // тут 1,2 так как в БД было только 2 записи
$sql = mysqli_query ($db, "SELECT a.*, q.* FROM `question` q 
INNER JOIN `answer` a ON q.q_id = a.q_id
WHERE q.q_id='".$rand."' AND a.a_correct = 1 OR a.a_correct = 0
LIMIT 4");
while ($row = mysqli_fetch_assoc($sql)) {
    echo $row['q_quest']." ".$row['a_answer']."<br>";
}

$rand = rand(1,2);  // тут 1,2 так как в БД было только 2 записи
$sql = mysqli_query ($db, "SELECT a.*, q.* FROM `question` q 
INNER JOIN `answer` a ON q.q_id = a.q_id
WHERE q.q_id='".$rand."' 
AND (a.a_correct = 1 OR a.a_correct = 0)  ORDER BY RAND()
LIMIT 4");
while ($row = mysqli_fetch_assoc($sql)) {
    echo $row['q_quest']." ".$row['a_answer']."<br>";
}

$q_id = rand(1,5);
 
$query = "(SELECT q.q_id, q.q_quest, a.a_id, a.a_answer, a.a_correct
                FROM answer a 
                INNER JOIN question q USING(q_id) WHERE a.a_correct=1 AND q_id=$q_id  LIMIT 1)
                    UNION 
            (SELECT q.q_id, q.q_quest, a.a_id, a.a_answer, a.a_correct
                FROM answer a 
                INNER JOIN question q USING(q_id) WHERE a.a_correct=0 AND q_id=$q_id ORDER BY RAND() LIMIT 3)
             ORDER BY RAND()
                            ";