Table schema:
CREATE TABLE student (stuid VARCHAR, major VARCHAR); CREATE TABLE member_of_club (clubid VARCHAR, stuid VARCHAR); CREATE TABLE club (clubname VARCHAR, clubid VARCHAR)

Question: Which club has the most members majoring in "600"?
SQL: SELECT t1.clubname FROM club AS t1 JOIN member_of_club AS t2 ON t1.clubid = t2.clubid JOIN student AS t3 ON t2.stuid = t3.stuid WHERE t3.major = "600" GROUP BY t1.clubname ORDER BY COUNT(*) DESC LIMIT 1