Cindy, a Production Red is not a sex link. Exactly what it is depends on which hatchery it comes from, but they are red chickens. One hatchery claims theirs are Rhode Island Reds crossed with New Hampshires, for example, but others produce Production Reds differently. It is just a sales name that should signify a hen that will lay well and is probably a cross of some type. But they should not be a sex link.
One of those has a comb and wattles much more developed than the others. The comb and wattles look a little redder too. I agree a full body shot, including the legs, would help us be more sure, but that one does look rooish to me.
1Hawaiian, if that one has legs heavier than the others, I'd really guess roo.