Consider the tables advisors and students given below.
CREATE TABLE `advisors` ( `advisor_id` int(11) NOT NULL AUTO_INCREMENT, `first_name` varchar(255) NOT NULL, `last_name` varchar(255) NOT NULL, PRIMARY KEY (`advisor_id`) ) CREATE TABLE `students` ( `student_id` int(11) NOT NULL AUTO_INCREMENT, `first_name` varchar(255) NOT NULL, `last_name` varchar(255) NOT NULL, `advisor_id` int(11) DEFAULT NULL, PRIMARY KEY (`student_id`), KEY `advisor_id` (`advisor_id`), CONSTRAINT `students_ibfk_1` FOREIGN KEY (`advisor_id`) REFERENCES `advisors` (`advisor_id`) );
Which of the following query can you use to get the information on students and their advisors, excluding students who are not assigned to an advisor?