Naze Hito wa Arasoun Darou? / Summer Wind / Jinsei wa STEP! (何故 人は争うんだろう？／Summer Wind／人生はSTEP!; Why Do People Compete? / Summer Wind / Life is a STEP!) is ℃-ute's 29th single. It was released on April 20, 2016 in 6 editions: 3 regular and 3 limited editions. The first press of the regular editions come with a random trading card of 6 kinds depending on the jacket (18 total). The limited editions come with an event lottery serial number card.