B1A4 is a South Korean boy band under the management of WM Entertainment that debuted in 2011. The group's name has a connection with the members' blood types. Members Jinyoung, CNU, Sandeul and Gongchan are type A and member Baro is a type B, hence the numbers 4 and 1 to make the group name "B1A4". "Be the one All for one“ is another explanation concerning the group's name meaning that they'll do their best as what everyone expects them to.
Filmography: SBS MTV Special