 
<translate> Passage: Tata Sons Limited bụ ụlọ ọrụ na-ejide ụlọ ọrụ nke Tata Group ma na-ejide akụkụ ka ukwuu nke ụlọ ọrụ ndị a. E guzobere ya dị ka ụlọ ọrụ azụmaahịa na 1868. Ihe dị ka 86% nke isi obodo nke Tata Sons bụ nke ndị ọrụ ebere tụkwasịrị obi site n'aka ndị otu ezinụlọ Tata. Abụọ n'ime ndị a tụkwasịrị obi bụ Sir Dorabji Tata Trust na Sir Ratan Tata Trust. Tata Sons bụ onye nwe aha Tata na akara ụghalaahịa Tata, bụ́ ndị e debara aha ha n'akwụkwọ n'India na n'ọtụtụ mba ndị ọzọ. TCS naanị na-ewepụta 70% nke ego ụlọ ọrụ nne ya, Tata Sons. Natarajan Chandrasekaran weghaara dịka onye isi oche nke Tata Sons na 21 Febụwarị 2017.  Ajụjụ: Dabere n'okwu a, onye ga-abụ onyeisi oche nke tata sons n'afọ 2017? Steam nke ịmara n'okpuru: <eng> Passage: Tata Sons Limited is the holding company of the Tata Group and holds the bulk of shareholding in these companies. It was established as a trading enterprise in 1868. About 86 % of the equity capital of Tata Sons is held by philanthropic trusts endowed by members of the Tata family. The biggest two of these trusts are the Sir Dorabji Tata Trust and Sir Ratan Tata Trust. Tata Sons is the owner of the Tata name and the Tata trademarks, which are registered in India and several other countries. TCS alone generates 70 % revenues of its parent company, Tata Sons. Natarajan Chandrasekaran took over as Chairman of Tata Sons on 21 February 2017.

Question: Based on this passage, who become the chairmen of tata sons in 2017?
Steam of consciousness below:
 