The correct statements about metal carbonyls are
A. The metal-carbon bonds in metal carbonyls possess both $$\sigma$$ and $$\pi$$-character.
B. Due to synergic bonding interactions between metal and CO ligand, the metal-carbon bond becomes weak.
C. The metal-carbon $$\sigma$$ bond is formed by the donation of lone pair of electrons on the carbonyl carbon into a vacant orbital of metal.
D. The metal-carbon $$\pi$$ bond is formed by the donation of electrons from filled d-orbital of metal into vacant $$\pi^*$$ orbital of CO.
Choose the correct answer from the options given below: