In the product $6 O _2$, what does the coefficient mean?
AThere are 12 molecules of $O _2$.
BThere are 8 molecules of $O _2$.
CThere are 6 molecules of $O _2$.
DThere are 2 molecules of $O _2$.
AThere are 12 molecules of $O _2$.
BThere are 8 molecules of $O _2$.
CThere are 6 molecules of $O _2$.
DThere are 2 molecules of $O _2$.