The correct answer is: A. drag the primary key of a table into foreign key of another table.
A primary key is a column or group of columns that uniquely identifies each row in a table. A foreign key is a column or group of columns in one table that refers to the primary key of another table.
To create a relationship between two tables, you need to create a foreign key in the child table that references the primary key of the parent table. For example, if you have a table of customers and a table of orders, you would create a foreign key in the orders table that references the customer ID column in the customers table. This would ensure that each order in the orders table is associated with a customer in the customers table.
Option B is incorrect because you cannot drag the foreign key of a table into the primary key of another table. The foreign key must reference the primary key of the parent table.
Option C is incorrect because you cannot drag any field from a parent table and drop it on a child table. The field that you drag must be the primary key of the parent table or a foreign key that references the primary key of the parent table.
Option D is incorrect because only option A is correct.