This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Passage: Burdened with debt, in 2004 Vivendi Universal sold 80% of Vivendi Universal Entertainment (including the studio and theme parks) to General Electric, parent of NBC. The resulting media super-conglomerate was renamed NBCUniversal, while Universal Studios Inc. remained the name of the production subsidiary. After that deal, GE owned 80% of NBC Universal; Vivendi held the remaining 20%, with an option to sell its share in 2006. GE purchased Vivendi's share in NBCU in 2011 and in turn sold 51% of the company to cable provider Comcast. Comcast merged the former GE subsidiary with its own cable-television programming assets, creating the current NBCUniversal. Following Federal Communications Commission (FCC) approval, the Comcast-GE deal was closed on Jan 29, 2011. In March 2013, Comcast bought the remaining 49% of NBCUniversal for $16.7 billion. Question: In what month and year did Comcast buy 49% of NBCUniversal?
March 2013