https://www.gamespot.com/articles/xbox-one-adds-new-backwards-compatible-game/1100-6461437/

Microsoft has added another game to Xbox One's steadily growing backwards compatible library. Only one new Xbox 360 title is playable on the current-gen console this week, but it's one of the system's most popular: Call of Duty: Modern Warfare 2.

Originally released in 2009, Modern Warfare 2 was one of the most acclaimed entries of its generation and was one of the installments responsible for propelling the Call of Duty series to its current popularity. GameSpot awarded the Xbox 360 version a 9/10 in our Modern Warfare 2 review and called it "a thoroughly excellent package that is sure to thrill shooter fans and deprive them of sleep for months to come."