The radical which mainly causes ozone depletion in the presence of UV radiations is :

The main radical responsible for ozone depletion in the presence of UV radiation is the chlorine radical (Cl•).

The mechanism of ozone depletion by chlorine radicals:

CFCs (chlorofluorocarbons) release chlorine atoms when exposed to UV radiation in the stratosphere:

$$\text{CF}_2\text{Cl}_2 \xrightarrow{UV} \text{CF}_2\text{Cl}^\bullet + \text{Cl}^\bullet$$

The chlorine radical then catalytically destroys ozone:

$$\text{Cl}^\bullet + \text{O}_3 \to \text{ClO}^\bullet + \text{O}_2$$

$$\text{ClO}^\bullet + \text{O} \to \text{Cl}^\bullet + \text{O}_2$$

A single chlorine radical can destroy thousands of ozone molecules.

The answer is Option 1: Cl•.