Identify the adjective (Visheshana) among the given words:

Let's analyze the parts of speech of all the given choices:
* जाना (Jaana): A verb ($\text{Kriya}$), representing an action.
* देवता (Devta): A noun ($\text{Sangya}$), naming a class of divine beings.
* कौन (Kaun): An interrogative pronoun ($\text{Prashnavachak Sarvanam}$).
* सुन्दर (Sundar): An adjective (विशेषण), as it describes the characteristic quality or beauty of a noun or pronoun (e.g., सुन्दर फूल - beautiful flower).