Given below are two statements: one is labelled as "Assertion A" and the other is labelled as "Reason R" Assertion A: In the complex Ni ( CO )_4 and…

Given below are two statements: one is labelled as "Assertion A" and the other is labelled as "Reason R"Assertion A: In the complex $\displaystyle \mathrm{Ni}(\mathrm{CO})_4$ and $\displaystyle \mathrm{Fe}(\mathrm{CO})_5$, the metals have zero oxidation state.Reason R: Low oxidation states are found when a complex has ligands capable of $\displaystyle \pi$-donor character in addition to the $\displaystyle \sigma$-bonding.In the light of the above statements, choose the most appropriate answer from the options given below