Which of these is correct about passing an argument by call-by-value process?

• A. Copy of argument is made into the formal parameter of the subroutine
• B. Reference to original argument is passed to formal parameter of the subroutine
• C. Copy of argument is made into the formal parameter of the subroutine and changes made on parameters of subroutine have effect on original argument
• D. Reference to original argument is passed to formal parameter of the subroutine and changes made on parameters of subroutine have effect on original argument