In the same patient–blood grouping shows A negative, with an anti D antibody titer of 1:4- the most appropriate next step in the management –Since this patient is a primi patient and her antibody titre is 1:4 so we should follow it by doing a repeat titre after every 4 weeks. If this pregnancy would not have been her first affected pregnancy, then amniocentesis i.e. option a would have been the correct response.