QUESTION 9 Suppose we wanted to add students to the database of hw2, along with the grades they have got in the sections they enrolled in. For the relational model how would we do this? a. Add a table for Person with a netid (key) and other attributes, including one grade attribute for each course the Student has taken Add a foreign key to the Person table to reference the sections the person has enrolled in O b. Add a table for person with a netid (key) and other attributes, including one grade attribute for each course the Student has taken O c. Add a table for Person with a netid (key) and other attributes Add a foreign key to the Section table to reference the students who are taking the section Add a grade attribute to the Person table O d. Add a table for Person with a netid (key) and other attributes Add a relationship table that references a Person as the student and a Section as the section the student enrolls in Add a grade attribute to this relationship table