Given a text passage, come up with an appropriate title for it. The title should accurately represent what the main focus of the passage is. The title of a passage may be present in the first few sentences of the passage and/or be referred to multiple times in the passage. The title should be 1-5 words long.

[Q]: Super Smash Bros. was introduced in 1999 for the Nintendo 64 . It was released worldwide after selling over a million copies in Japan . It featured eight characters from the start ( Mario , Donkey Kong , Link , Samus , Yoshi , Kirby , Fox , and Pikachu ) , with four unlockable characters ( Luigi , Captain Falcon , Ness , and Jigglypuff ) , all of them created by Nintendo or one of its second - party developers .
[A]: Super Smash Bros.

[Q]: '' Big Iron '' is a country ballad written and performed by Marty Robbins , originally released as an album track on Gunfighter Ballads and Trail Songs in September 1959 , then as a single in February 1960 with the song '' Saddle Tramp '' as the B - side single . Members of the Western Writers of America chose it as one of the Top 100 Western songs of all time .
[A]: Big Iron

[Q]: Blood urea nitrogen ( BUN ) is a medical test that measures the amount of urea nitrogen found in blood . The liver produces urea in the urea cycle as a waste product of the digestion of protein . Normal human adult blood should contain between 6 and 20 mg of urea nitrogen per 100 ml ( 6 -- 20 mg / dL ) of blood . Individual laboratories will have different reference ranges as the assay used will vary between laboratories .
[A]:
Blood urea nitrogen