`[FeF_(6)]^(3-)` is paramagnetic due to presence of unpaired electrons in the complex . The five electrons remain unpaired because
A. fluorine is the most electronegative element
B. `F^(-)` is a weak field ligand hence does not cause pairing of electrons
C. `F^(-)` is a strong field ligand hence does not cause pairing of electron
D. pairing does not take place in iron complexes .