Premise: Boyz II Men is an American R&B vocal group from Philadelphia , Pennsylvania , best known for emotional ballads and acappella harmonies . Formerly a quartet including bass Michael McCary , they are currently a trio composed of baritone Nathan Morris alongside tenors Wanya Morris and Shawn Stockman . In music , a quartet or quartette is an ensemble of four singers or instrumental performers ; or a musical composition for four voices or instruments .
Hypothesis: Boyz II Men uses their voice as instruments.
Label: ENTAILMENT