A pregnant lady at 10 weeks pregnancy is found to have Anti D Red cell antibodies. She has separated from her partner and his blood group cannot be found out. What other test can be offered earliest to her to check if the fetus is at risk of HDFN Hemolytic disease of fetus and newborn) –

A. Maternal Genotyping

B. Fetal Genotyping with cell free Fetal DNA

C. Fetal Ultrasound with Doppler

D. Pre-implantation genetic diagnosis