What is the level of the course with the most number of teachers?
level of the course refers to courseLevel; course with most number of teachers refers to course_id = max(count(taughtBy.p_id))
SELECT T1.courseLevel FROM course AS T1 INNER JOIN taughtBy AS T2 ON T1.course_id = T2.course_id GROUP BY T2.course_id ORDER BY COUNT(T2.p_id) DESC LIMIT 1
database name:db_id computer_student
course table course Cols: course id dtype integer, course level dtype text, 
person table person Cols: person ID dtype integer, professor dtype integer, student dtype integer, has position dtype text, in phase dtype text, years in program dtype text, 
advisedBy table advisedBy Cols: person id dtype integer, person id dummy dtype integer, 
taughtBy table taughtBy Cols: course ID dtype integer, person ID dtype integer, 
