Most Popular Courses

Return the course title(s) with the highest number of enrolled students (include ties).

Table schema

Students(id INT PRIMARY KEY, name VARCHAR(10))
Courses(id INT PRIMARY KEY, title VARCHAR(10), credits INT)
Enrollments(student_id INT, course_id INT, grade_points INT)

Sample data

Students
id | name
1 | Ann
2 | Bob
3 | Cy

Courses
id | title | credits
10 | Math | 4
20 | Physics | 3
30 | Art | 2

Enrollments
student_id | course_id | grade_points
1 | 10 | 4
1 | 20 | 3
1 | 30 | 4
2 | 10 | 2
2 | 20 | 3
3 | 10 | 3