Question: In Resident Evil 5, which character investigates a terrorist threat while simultaneously looking for his missing younger sister, Claire?
Context: Resident Evil 5, known in Japan as Biohazard 5, is a third-person shooter video game developed and published by Capcom and released in 2009.  It is the seventh major installment in the "Resident Evil" series, and was announced in 2005—the same year its predecessor "Resident Evil 4" was released.  "Resident Evil 5" was released for the PlayStation 3 and Xbox 360 consoles in March 2009 and for Microsoft Windows in September that year.  The plot involves an investigation of a terrorist threat by Bioterrorism Security Assessment Alliance (BSAA) agents Chris Redfield and Sheva Alomar in Kijuju, a fictional region of Africa.  Redfield soon learns that he must confront his past in the form of an old enemy, Albert Wesker, and his former partner, Jill Valentine. Sheva Alomar (シェバ・アローマ , Sheba Arōma ) is a fictional character in the "Resident Evil" horror video game series by Capcom.  She was introduced in 2009's "Resident Evil 5" as a native African operative of the Bioterrorism Security Assessment Alliance (BSAA) and a new partner of the series' veteran Chris Redfield.  The character was met with mostly positive reception, but has not yet returned for any further installment of the series. Claire Redfield (クレア・レッドフィールド , Kurea Reddofīrudo ) is a fictional character in the "Resident Evil" ("Biohazard" in Japan) horror franchise by Capcom.  Claire is the younger sister of Chris Redfield, an American special police officer who is a protagonist of the first "Resident Evil" game, and is herself a protagonist of the video games "Resident Evil 2" and "", where she is a zombie outbreak survivor turned a vigilante.  She returned as an abducted activist in the video game "" after being absent from the main series for a decade and half since "Code: Veronica". Leon Scott Kennedy (レオン・スコット・ケネディ , Reon Sukotto Kenedi ) is a fictional character in the "Resident Evil" horror media franchise by Capcom.  He debuted as one of the two playable protagonists of the video game "Resident Evil 2".  Leon later returned as the protagonist of "Resident Evil 4" and as one of the six protagonists in "Resident Evil 6".  The character was met with positive critical reception. Resident Evil: The Mercenaries 3D, known as "Biohazard: The Mercenaries 3D" (Japanese: バイオハザード ザ・マーセナリーズ 3D , Hepburn: Baiohazādo za Māsenarīzu 3D ) in Japan, is a third-person shooter video game developed by Capcom for the Nintendo 3DS and the 18th installment of the "Resident Evil" series.  The game was announced at the 2010 Nintendo conference in Japan.  A combination of the "Mercenaries" minigames featured in "Resident Evil 4" and "Resident Evil 5", players must defeat as many enemies as possible within a set time limit. Resident Evil: Revelations 2, known in Japan as Biohazard Revelations 2 (バイオハザード リベレーションズ 2 , Baiohazādo Riberēshonzu Tsū ) , is an episodic survival horror video game developed and published by Capcom.  It is the tenth major installment in the "Resident Evil" franchise (22nd overall).  The game is a follow up to "" and "Resident Evil 5".  The game marks the return of Claire Redfield as the main protagonist, and the first time Barry Burton is a playable story character in the main series.  The first installment was released in February 2015. Resident Evil: Mercenaries Vs. was released on April 14, 2011.  The game and the enemies are based on "Resident Evil 4", but the characters are based on "Resident Evil 5".  It is the first "Resident Evil" multiplayer for iOS (17th overall in the series), and supports a two-versus-two online team match mode, "Free for all" mode (via Wi-Fi, Internet, or Bluetooth), or a one-versus-one team mode.  It also supports a single-player mode. Jun Takeuchi (竹内 潤 , Takeuchi Jun , born August 24, 1970 in Toyonaka, Osaka) is a Japanese video game director and producer.  He graduated from the Division of Graphics at the Sozosha College of Design and joined the game development company Capcom in 1991.  He served as the producer for "Onimusha 3" and "Lost Planet" and chief producer for "Resident Evil 5".  Takeuchi has also worked on other Capcom games such as "Street Fighter II" for the Super Nintendo Entertainment System and "Resident Evil" and "Resident Evil 2" for the PlayStation. Resident Evil: Revelations, known as "Biohazard Revelations" (Japanese: バイオハザード リベレーションズ , Hepburn: Baiohazādo Riberēshonzu ) in Japan, is a survival horror video game developed by Capcom and originally released for the Nintendo 3DS handheld game console in early 2012.  It is part of the "Resident Evil" video game series and takes place between the events of "Resident Evil 4" and "Resident Evil 5".  The story of the game follows series protagonists Jill Valentine and Chris Redfield as they try to stop a bioterrorist organization from infecting the Earth's oceans with a virus. He is also one of the two protagonists of the game "", in which he looks for his missing younger sister, Claire, and one of the main characters of "", where he manages to take down the Umbrella Corporation with Jill.  Chris returned as the main protagonist of "Resident Evil 5", working alongside his new partner Sheva Alomar, and is one of the main protagonists in the game, "."  Chris returns as one of four protagonists in "Resident Evil 6" where he and his partner Piers Nivans attempt to stop a worldwide bio-terrorism attack.  He also has a cameo appearance at the end of "" and will star in its downloadable campaign, "Not a Hero", where he leads a revised, benevolent Umbrella Corporation team, in search of the villainous Lucas Baker, while also having to battle hordes of more aggressive "Molded" creatures.
Answer: Chris Redfield