The coordination number of a central metal atom in a complex is determined by:
A. (a) The number of only anionic ligard bonded to metal ion.
B. (b) the number of ligands around a metal ion bonded by sigma bonds.
C. (c) the number of ligands around a metal ion bonded by pi bonds.
D. (d) the number of ligands around a metal ion bonded by sigma and pi bonds.
