 <translate> 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:
 <yor> Passage: Tata Sons Limited ni ile-iṣẹ idaduro ti Tata Group ati pe o ni ọpọlọpọ awọn ipin ninu awọn ile-iṣẹ wọnyi. A ti fi idi rẹ mulẹ bi ile-iṣẹ iṣowo ni ọdun 1868. O fẹrẹ to 86% ti olu-ilu inifura ti Tata Sons ni o wa nipasẹ awọn igbẹkẹle onigbọwọ ti o funni nipasẹ awọn ọmọ ẹgbẹ ti ẹbi Tata. Awọn meji ti o tobi julo ninu awọn igbẹkẹle wọnyi ni Sir Dorabji Tata Trust ati Sir Ratan Tata Trust. Tata Sons ni ẹni tó ni orúkọ Tata àti àwọn àmì ọjà Tata, tí wọ́n forúkọ sílẹ̀ ní Íńdíà àti ní àwọn orílẹ̀-èdè mìíràn. TCS nìkan ni ó ń mú 70% owó wọlé fún ilé-iṣẹ́ ìyá rẹ̀, Tata Sons. Natarajan Chandrasekaran gba ipo alaga ti Tata Sons ni ọjọ 21 Kínní 2017.  Ìbéèrè: Ní ìbámu pẹ̀lú àyọkà yìí, ta ni yóò di alága àwọn ọmọ tata ní ọdún 2017? Ìrì ìmọ̀lára ní ìsàlẹ̀: 