Professor A runs three projects with five master students. Some students are assigned to multiple projects. Professor B runs four projects with ten students. Each student is assigned to only one project, whereas some projects can have multiple students.

In case of Professor A$,$ where is the foreign key $($FK$)$ located between project table and student table?

one:

a$.$ Doesn$$t need FK because it does not need the project table

b$.$ Doesn$$t need FK because it does not need the student table

c$.$ Associative entity

d$.$ Student table

e$.$ Project table