"who" is one of those words that can, in and of itself, be singular or plural. the context in which it is used determines the outcome
ex
who in relation to "out they go" - plural
who in relation to "out he goes" - singular
"who" is one of those words that can, in and of itself, be singular or plural. the context in which it is used determines the outcome
ex
who in relation to "out they go" - plural
who in relation to "out he goes" - singular