How are transformants selected from non-transformants?

• A

  Presence of more than one recognition site in the vector DNA.
• B

  Presence of alien DNA into the vector DNA results into insertional inactivation of selectable marker.
• C

  Antibiotic resistance gene gets inactivated due to insertion of alien DNA.
• Correct answer
  D

  Both (b) and (c).

Hence, the correct answer is option: 'D'.