Explanation:

- Option 4: Akbar

- Tansen, a legendary musician, was a part of Akbar's court in the 16th century.

- He is celebrated for his contributions to Hindustani classical music.

- Option 1: Ashoka

- Ashoka was an emperor of the Maurya Dynasty, ruling in the 3rd century BCE.

- He is known for spreading Buddhism after the Kalinga War.

- Option 2: Chandragupta

- Chandragupta Maurya founded the Maurya Empire in the 4th century BCE.

- Notably, he unified most of the Indian subcontinent.

- Option 3: Shah Jehan

- Shah Jehan was the 5th Mughal emperor, known for building the Taj Mahal.

- His reign was in the 17th century, after Tansen's time.