Question: Shashikala Dani is the only All India Radio graded female exponent of an instrument that consists of what ?
Context: The Iyer brothers are two twin brothers, Ramnath Iyer and Gopinath Iyer, who are veena exponents from Melbourne, Australia.  The brothers have been performing together since 1994 and they have been received very well globally.  They are ‘A’ graded artists of All India Radio, Chennai. O. S. Thiagarajan (born April 3, 1947) is a Carnatic Musician based in Chennai.  He is the son and disciple of Sangeetha Booshanam O.V.Subrahmanyam.  He learnt music from Sangeetha Kalanidhi T.M. Thygarajan, while Padmabhushan Lalgudi Jayaraman provided guidance/mentorship early in his career.  An ‘A- Top’ graded artist of the All India Radio and of Doordarshan, he has been giving a large number of concerts well appreciated and relished.  He is regularly featured by all leading sabhas in Chennai as well as throughout India and has been accompanied by top accompanists such as Lalgudi Shri.G.Jayaraman, M.S. Gopalakrishnan , V.V. Subrahmanyam on violin, Palghat Mani Iyer,Dr T.K.Murthy, Palghat Raghu, Karaikudi Mani, Trichy Sankaran, Umayalpuram Sivaraman on mridanagm, Shri.G Harishankar on Kanjira and Vikku Vinayakaram on Ghatam.  He has toured many countries, including USA, Canada, Australia, Singapore, Middle East, Malaysia, Hong Kong, South Africa, and many cities in Europe.  He worked as Dean, Faculty of Fine Arts, and Annamalai University for 5 years.  He has trained many disciples who are active on the concert circuit. All India Radio (AIR), officially known since 1956 as Ākāshvāṇī (Sanskrit: आकाशवाणी; "Voice from the Sky"), is the national public radio broadcaster of India and a division of Prasar Bharati.  Established in 1930, it is the sister service of Prasar Bharati's Doordarshan, the national public television broadcaster.  AIR has covered more than 99% of the Indian population as per the latest information given by Minister of Information and Broadcast.  All India Radio is the largest radio network in the world.  Its headquarters is at the Akashvani Bhavan in New Delhi.  Akashvani Bhavan houses the Drama Section, the FM Section and the National Service.  Akashvani Bhavan hosts Doordarshan Kendra (Delhi). Seetha Doraiswamy (Tamil: சீதா துரைசாமி, "sītā turAisvāMī"  27 January 1926 – 14 March 2013), commonly known as Madisaar Maami, was a renowned Carnatic multi-instrumentalist.  She was the last recognised female exponent of a dying Indian instrument, the jal tarang.  She was the first (and till date youngest) female musician ever to be awarded the Gold Medal of Honour from The Music Academy, the first Carnatic music Institute.  She is the only Jal Tarang exponent to have ever received the Kalaimamani award, India's fourth highest civilian award, in 2001 with the citation reading "(Seetha) has tirelessly worked to prevent the jalatharangam from becoming extinct and is often recognized only for that; it is time to bring to notice the fact that she championed for the cause of equal female representation during a time where our cultural norms may have not.  Additionally, her theoretical knowledge was the foundation for many of the modern concepts of Carnatic music as we know it today." Jawhar Sircar (born March 22, 1952) was the Chief Executive Officer, equivalent to the position of Secretary, Govt.  of India, of Prasar Bharati, India's Public Service Broadcaster that is All India Radio and Doordarshan.  He supervisedthe two broadcasting networks of India: All India Radio (AIR) & Doordarshan (TV); among the three largest in the world. Archana Udupa (Tulu: ಅರ್ಚನ ಉಡುಪ ) is an Indian singer.  She sings devotional, classical and film songs.  She is graded artist of All India Radio and Doordarshan.  She won Zee TV TVS Sa Re Ga Ma Pa contest of singing in 1998.  Archana Udupa is the first person of south Indian origin to win Hindi film song singing contest.  As of now she has sung in more than 1000 cassettes and CDs (Albums). Aurora Reyes Flores (born in Hidalgo del Parral, September 9, 1908 – Mexico City, April 26, 1985) was a Mexican painter and writer, as well as the first female exponent of Mexican muralism.  She also went by the name Aurora Reyes. Vidushi Shashikala Dani (Kannada: ಶಶಿಕಲಾ ದಾನಿ, ""  |Hindi: शशिकला दानी, "Shashikalā Dāni"  ) is an Indian Hindustani Classical Multi-Instrumentalist.  She is one of the few artists and presently the only All India Radio graded female exponent of a unique Indian instrument, Jaltarang (Kannada: ಜಲ ತರಂಗ, ""  |Hindi: जल तरंग, ""  ). The jal tarang (Hindi: जल तरंग, Urdu: ‎ , ] ), Tamil: ஜலதரங்கம் , jaltarang, jal-tarang, jal-yantra, jalatarangam or jalatharangam is an Indian melodic percussion instrument.  It consists of a set of ceramic or metal bowls tuned with water.  The bowls are played by striking the edge with beaters, one in each hand. Darius Sunawala (born 05-Jan-1979) has been one of Bangalore's most popular RJs.  He used to host an evening radio show called Route 91 followed by a request show called Top 8@8.  Although Sunawala became famous while he was with Radio City 91 FM he had previously worked with All India Radio and Indigo (when it was on the WorldSpace receiver).  In 2000, Sunawala abandoned a successful course of M.B.A. studies halfway through in order to take up a radio career with All India Radio.
Answer: a set of ceramic or metal bowls tuned with water