(SELECT answers.*, response_options.*, 
 IF((SELECT dependencies.answerid FROM dependencies WHERE dependencies.questionid = 5 LIMIT 1) IS NOT NULL, (SELECT dependencies.targetid FROM dependencies, answers WHERE dependencies.answerid = answers.id LIMIT 1), NULL) AS target

 
FROM answers, response_options WHERE response_options.questionid = 5 AND answers.id = response_options.answerid);