To match the elements from List I with their corresponding properties in List II, let's analyze each pair:

A. $$\mathrm{Cl,S}$$

These elements are known for having high negative electron gain enthalpy (energy released when an electron is added to an atom). Chlorine ($$\mathrm{Cl}$$) and sulfur ($$\mathrm{S}$$) are both elements that release a significant amount of energy when they gain an electron.

Hence, they match with IV: Elements with highest negative electron gain enthalpy.

B. $$\mathrm{Ge,As}$$

Germanium ($$\mathrm{Ge}$$) and arsenic ($$\mathrm{As}$$) are metalloids, meaning they show properties of both metals and non-metals.

Hence, they match with III: Elements which show properties of both metals and non-metal.

C. $$\mathrm{Fr,Ra}$$

Francium ($$\mathrm{Fr}$$) and radium ($$\mathrm{Ra}$$) are elements that have very large atomic sizes, being at the bottom of their respective groups on the periodic table.

Hence, they match with II: Elements with largest atomic size.

D. $$\mathrm{F,O}$$

Fluorine ($$\mathrm{F}$$) and oxygen ($$\mathrm{O}$$) are elements with the highest electronegativity, meaning they strongly attract electrons toward themselves.

Hence, they match with I: Elements with highest electronegativity.

Summarizing, we have:

A-IV, B-III, C-II, D-I

The correct option is:

Option D

A-IV, B-III, C-II, D-I