In which one of the following clinical situations is the prophylactic use of antibiotics NOT warranted.. It is contraindicated in pregnancy

In which one of the following clinical situations is the prophylactic use of antibiotics NOT warranted:
A) It is useful for the treatment of resistant strains
B) It is contraindicated in pregnancy***
C) It is effective in infection caused by Chlamydia
D) Patient with a heart prosthesis having a tooth removal.