Explanation:

- Option 1: Chandragupta I

- Chandragupta I was a ruler from the Gupta dynasty but is not associated with Harisena.

- Option 2: Chandragupta II

- Chandragupta II was known for his patronage of scholars, yet Harisena was not his court poet.

- Option 3: Samudragupta

- Harisena was indeed the court poet of Samudragupta. He played a crucial role in documenting Samudragupta's achievements through inscriptions, notably the Allahabad Pillar inscription.

- Option 4: None of the above

- This option is incorrect as Harisena was a known historical figure associated with Samudragupta.