Question: Where is the company who released Uno for Game Boy Color headquartered?

Context paragraphs:
Uno (handheld game): Uno is a game for the Game Boy Color based on the card game of the same name.  It was released by Mattel Games on December 16, 1999.

Dragon Warrior Monsters 2: Dragon Warrior Monsters 2, known in Japan as Dragon Quest Monsters 2 (ドラゴンクエストモンスターズ , Doragon Kuesuto Monsutāzu Tsū ) , is a role-playing video game published by Enix for the Game Boy Color.  It is the second "Dragon Warrior Monsters" game for the Game Boy Color and features two different versions of the same game, "Cobi's Journey" (released as "Dragon Quest Monsters 2: Ruka's Journey" in Japan) and "Tara's Adventure" (released as "Dragon Quest Monsters 2: Iru's Adventure" in Japan).  This was the last Game Boy Color title released in North America that was also compatible with the original Game Boy and enhanced for the Super Game Boy.

Harvest Moon GB: Harvest Moon GB (牧場物語GB , Bokujō Monogatari GB ) is the second game in the "Story of Seasons" series of video games, and was developed by Victor Interactive Software.  "Harvest Moon GB" is the first portable "Harvest Moon" game, developed for the Game Boy.  A Game Boy Color version was released later under the name Harvest Moon GBC.  The Game Boy Color version was later released on the 3DS Virtual Console in 2013.

Top Gear Rally: Top Gear Rally is a rally game for the Nintendo 64, Game Boy Color and Game Boy Advance.  The Game Boy Color version was released under the name Top Gear Pocket, although the European release uses the original name; the Game Boy Advance version was released in Japan under the game Top Gear Rally SP.  It features five tracks.  It has a feature that allows the user to give their virtual cars custom paint jobs.  Although the name stayed the same, the developers changed between consoles.  As a result, the games are very different depending on the platform, but they often have similar features such as the paint shop.

Mattel: Mattel, Inc. ( ) is an American multinational toy manufacturing company founded in 1945 with headquarters in El Segundo, California.  In 2014, it ranked #403 on the Fortune 500 list.  The products and brands it produces include Fisher-Price, Barbie dolls, Monster High dolls, Ever After High dolls, Winx Club dolls, Hot Wheels and Matchbox toys, Masters of the Universe toys, American Girl dolls, board games, and WWE toys.  In the early 1980's, Mattel produced video game systems, under its own brands and under license from Nintendo.  The company has presence in 40 countries and territories and sells products in more than 150 nations.  The company operates through three business segments: North America, international, and American Girl.  It is the world's largest toy maker in terms of revenue.  On January 17, 2017, Mattel named Google executive Margo Georgiadis as its next CEO.

Wario Land II: Wario Land II (ワリオランド2 盗まれた財宝 , Wario Rando Tsū: Nusumareta Zaihō , "Wario Land 2: The Stolen Treasure") is a platform game released for the Game Boy in 1998.  It was the last first-party title made for the Game Boy and was later remade to take advantage of the Game Boy Color hardware.  In this game, Wario has to recover his treasure from Captain Syrup and her Black Sugar Gang (formerly the Brown Sugar Pirates).  The Game Boy Color version was released on the 3DS Virtual Console in 2012.

Game Boy Micro: Game Boy Micro (ゲームボーイミクロ , Gēmu Bōi mikuro ) (stylized as Game Boy micro) is a handheld game console developed and manufactured by Nintendo.  It was first released in September 2005 as a compact redesign of the Game Boy Advance.  The system is the last console in the Game Boy line.  Unlike its predecessor, the Game Boy Micro lacks backward compatibility for Game Boy or Game Boy Color games.

Game Boy Player: The Game Boy Player (ゲームボーイプレーヤー , Gēmu Bōi Purēyā ) (DOL-017) is a device made by Nintendo for the Nintendo GameCube which enables Game Boy, Game Boy Color, or Game Boy Advance cartridges (although Super Game Boy enhancements are ignored) to be played on a television.  It was the last Game Boy-based add-on to a Nintendo console.  It connects via the high speed parallel port at the bottom of the GameCube and requires use of a boot disc to access the hardware.  Unlike devices such as Datel's Advance Game Port, the Game Boy Player does not use software emulation, but instead uses physical hardware nearly identical to that of a Game Boy Advance.

SpongeBob SquarePants: Legend of the Lost Spatula: SpongeBob SquarePants: Legend of the Lost Spatula is a platform action video game developed by Vicarious Visions and published by THQ for the Game Boy Color handheld video game console.  The game was released in the United States on March 14, 2001, and in Europe on May 4, 2001.  The game's story centers on SpongeBob SquarePants, a sea sponge who lives in the undersea town of Bikini Bottom and works for Mr. Krabs as the fry cook of the Krusty Krab fast food restaurant.  SpongeBob is destined to become the ocean's greatest fry cook, and must embark on a quest to retrieved a "golden spatula" from the Flying Dutchman, a pirate ghost.  The game features platforming-style gameplay, as well as many characters from the television series.  This is the only 8-bit SpongeBob game and the only SpongeBob video game on the Game Boy Color.  A sequel, was released in November 2001 for the PlayStation and Game Boy Advance.

List of best-selling Game Boy video games: The best-selling video game of all-time on the Game Boy and Game Boy Color is "Tetris".  First released in Japan on June 14, 1989, "Tetris" was often released as a pack-in game for the original Game Boy, and went on to sell in excess of 35 million units worldwide.  The second best-selling Game Boy games are "Pokémon Red", "Green" and "Blue", which sold over 31 million units combined, followed by the best-selling Game Boy Color games "Pokémon Gold" and "Silver", which sold over 23 million units in total.  The top five is rounded out by the platform's first "Super Mario" title, "Super Mario Land", which sold over 18 million copies worldwide, and "Pokémon Yellow", which has sold over 14 million units in total.

Supporting paragraphs: Uno (handheld game) Mattel
Answer: El Segundo, California