Name the first Odia poet who indicated the time at which the classical ragas were to be sung

Answer: Option A

Jayadeva was a very important poet in Odisha.
He wrote the famous Gita Govinda, a beautiful poem about Radha and Krishna.
What makes him special for this question is that he specified the time each classical raga (a kind of musical scale) should be sung in his Gita Govinda.
This was a new thing at the time and showed his deep understanding of music.

Let's look at the other options:

Mukundadeva, Sudevraja, and Goparaja were rulers or figures in Odisha's history, but they are not known for specifying the timing of ragas in their writings like Jayadeva did.

So, the answer is Jayadeva because he's the first Odia poet known for indicating when ragas should be sung.