Question: What is the program id and the summary of the degree that has the most students enrolled?
SQL: SELECT T1.degree_program_id ,  T1.degree_summary_name FROM Degree_Programs AS T1 JOIN Student_Enrolment AS T2 ON T1.degree_program_id  =  T2.degree_program_id GROUP BY T1.degree_program_id ORDER BY count(*) DESC LIMIT 1