Concept:
According to ancient musicology treatises like Bharata's Natyashastra, musical instruments are universally categorized into four major classifications, known as the Four Vadya Varg:
• Tat Vadya (तत् वाद्य) – Chordophones or stringed instruments where sound is produced via vibrating strings.
• Avanaddha Vadya (अवनद्ध वाद्य) – Membranophones or percussion instruments covered with skin/membrane.
• Sushir Vadya (सुषिर वाद्य) – Aerophones or wind instruments utilizing air columns.
• Ghan Vadya (घन वाद्य) – Idiophones or solid instruments made of metal/wood that resonate without membranes.
The question asks specifically for stringed instruments (Tat Vadya).
Step 1: Evaluate each instrument based on its scientific acoustic design.
Let us analyze all the instruments present in the options:
• A. Swar Mandal: A classical plucked multi-string zither instrument used prominently for providing open melodic background drone support to vocalists. Since it relies entirely on strings, it is a Tat Vadya.
• B. Dimdimi: A traditional small hand-held folk percussion drum instrument enclosed by a thin skin membrane. It belongs to the Avanaddha Vadya category.
• C. Sarod: A premier classical plucked stringed instrument known for its continuous deep fretless metal fingerboard resonance. Since it uses plucked steel strings, it is a prominent Tat Vadya.
• D. Ghadas: Also sometimes transcribed or linked with earthen resonance bodies or primary metallic rhythmic blocks, it operates primarily as a solid structure or percussion support device under Ghan Vadya or folk percussion.
• E.] Pavika: A traditional wind-blown pipe or flute-type structure common in regional classical folk art, classifying it as a Sushir Vadya.
Step 2: Select the valid combination matching the criteria.
From the breakdown above, only Swar Mandal (A) and Sarod (C) belong to the string family. This matches the combination choice shown in option (B).