Which of the following is not performed as a task of natural join?

a$.$ If there are no common attributes, returns the relational product of the two tables

b$.$ Selects only the rows with common values in the common attribute$($s$)$

c$.$ If there are common attributes, returns the relational product of the two tables

d$.$ Determines the common attribute$($s$)$ by looking for attributes with identical names and compatible data types