Which is not true about metal carbonyls?

Ziegler-Natta catalyst is an organometallic compound of which metal?

The $V-C$ distance in $V(CO)_6$ and $[V(CO)_6]^-$ are respectively (in $pm$):

What is the nature of the $Fe-C$ bond in $Fe(CO)_5$?

Given below are two statements:
Statement $I$: The $M - C \sigma$ bond is formed by the donation of a lone pair of electrons on the carbonyl carbon into a vacant orbital of the metal.
Statement $II$: The $M - C \pi$ bond is formed by the donation of a pair of electrons from a filled $d$-orbital of the metal into the vacant antibonding $\pi^*$ orbital of carbon monoxide.
In the light of the above statements, choose the correct answer from the options given below:

The formula of the complex potassium trichloroethyleneplatinate $(II)$ is........