Match the properties given in List-I with the metals given in List-II…

The correct answer is Option (2) → (A)-(III), (B)-(I), (C)-(IV), (D)-(II)

List-I Property	List-II Metal
(A) 3d series element with highest melting point	(III) Cr
(B) element which can show +8 oxidation state	(I) Os
(C) 3d series element with largest number of oxidation states	(IV) Mn
(D) constituent of Mischmetall	(II) Fe

(A) 3d series element with highest melting point $\rightarrow$ (III) Cr (Chromium)

In the $3d$ transition series, melting points generally increase toward the middle of the series due to the involvement of a greater number of electrons from both $(n-1)d$ and $ns$ orbitals in interatomic metallic bonding. Chromium ($Cr$) has the highest melting point in the $3d$ series.

(B) Element which can show +8 oxidation state $\rightarrow$ (I) Os (Osmium)

Osmium is famous in inorganic chemistry for its ability to reach the $+8$ oxidation state, most notably in osmium tetroxide ($OsO_4$). While ruthenium also shows this state, Osmium is the classic example among the heavy transition metals.

(C) 3d series element with largest number of oxidation states $\rightarrow$ (IV) Mn (Manganese)

Manganese has the electronic configuration $[Ar] 3d^5 4s^2$. Because it has the maximum number of unpaired electrons in the $d$-subshell, it exhibits the widest range of oxidation states in the $3d$ series, ranging from $+2$ to $+7$.

(D) Constituent of Mischmetall $\rightarrow$ (II) Fe (Iron)

Mischmetall is an alloy consisting of rare earth elements (about $95\%$ Lanthanoids, mostly Cerium and Lanthanum) and about $5\%$ Iron ($Fe$), along with traces of $S$, $C$, $Ca$, and $Al$. It is commonly used in cigarette lighter flints.