Citadel Securities is buying Morgan Stanley’s unit focused on electronic market-making for US equity options. The move expands the firm’s already dominant role in the market. Bloomberg's Sridhar Natarajan joined Wall Street Beat on Open Interest to talk about the deal. -------- More on Bloomberg Television and Markets Like this video? Subscribe and turn on notifications so you don't miss any videos from Bloomberg Markets & Finance: https://tinyurl.com/ysu5b8a9 Visit http://www.bloomberg.com for