Final answer:
The correct answer is the join operation.
Step-by-step explanation:
The correct answer to the question is a. Join.
When using a relational database, the join operation allows a user to combine two or more tables based on a common column. This allows the user to see relevant data in a single view, as if it is in one big table.
For example, if you have a table of students and a table of courses, you can use the join operation to combine the two tables based on the student ID column, and see which students are enrolled in which courses.