Even though its comb is large, I'm leaning more towards pullet. I don't see any pointed tail, saddle, hackle, or wing bow feathers, and the general body shape is pullety. Also, leghorns develop larger combs than other breeds, so at 16 weeks, this size/redness of comb isn't entirely unusual.
Edited: Is that longer tail feather in the photos pointed? If so, it would be a sickle feather, and be a sign of a rooster.