Information about a collection of students is given by the relation…

Key idea: interpret each part of the expression step by step.

• Let F = π_studId(σ_sex = "female"(studInfo)). This is the set of all female student IDs.

• Let C = π_courseId(enroll). This is the set of all course IDs.

• F × C produces all pairs (femaleStudent, course) for every female and every course — i.e., the hypothetical relation where every female student is enrolled in every course.

• Subtracting enroll removes the pairs where the female student actually is enrolled. The remainder is the set of (femaleStudent, course) pairs where that female is not enrolled in that course.

• Projecting on courseId therefore yields all courses for which there exists at least one female student who is not enrolled in that course.

Conclusion: The expression returns course IDs whose enrolled female students form a proper subset of all female students (i.e., at least one female is not enrolled in the course).

Relation to the choices: The description 'Courses in which a proper subset of female students are enrolled' matches this meaning. The description 'Courses in which all the female students are enrolled' is the opposite; 'Courses in which only male students are enrolled' is inconsistent with the stated assumption that every course has at least one female student.