Explanation:

- Ustad Zakir Hussain is a world-renowned tabla virtuoso.

- Tabla: ?? The correct answer is Option 2. It's a traditional Indian percussion instrument that consists of a pair of hand-played drums. Ustad Zakir Hussain is highly acclaimed for his mastery over this instrument.

- Harmonium: This is a free reed instrument similar to a pump organ. It is often used in Indian classical music but is not Ustad Zakir Hussain's specialty.

- Santoor: A hammered dulcimer often played in Indian classical music, particularly in Kashmir, but not associated primarily with Zakir Hussain.

- Flute: A woodwind instrument played by blowing air across an opening. It is a significant part of Indian classical music but is not linked to Zakir Hussain.