Option 1, Harshacharita, is not correct as it was written by Banabhatta about Harshavardhana`s life. Option 2, Kadambari, is also incorrect because it was another work of Banabhatta written in classical Sanskrit.

The correct answer is Option 3, Ratnavali, which is one of the three plays authored by Harshavardhana himself. It is a Sanskrit drama that revolves around a romantic theme.

Option 4, Gitagovinda, is not correct because it is a highly esteemed lyrical poem in Sanskrit composed by the 12th-century poet, Jayadeva. It`s a work dedicated to Lord Krishna and was not authored by Harshavardhana.

So, the correct answer is Ratnavali, among these given options, it is the only work that was authored by Harshavardhana.