Explanation:

- Rajeev Janardan is a renowned musician known for playing an Indian classical instrument.

- He belongs to the Imdadkhani gharana, which is famous for its string instruments.

- Option 1: Tabla - The tabla is a percussion instrument, usually not associated with the Imdadkhani gharana.

- Option 2: Flute - The flute is a woodwind instrument and not typically linked with this gharana.

- Option 3: Harmonium - The harmonium is a keyboard instrument, not traditionally linked with the Imdadkhani gharana.

- Option 4: Sitar - The sitar is a plucked string instrument, commonly associated with the Imdadkhani gharana.

Correct Answer: Option 4 - sitar