answer:Whichever level leads to people maintaining common sense and keeping a handle on their damned kids and themselves. A kid I was once very close with died on Memorial Day. There was a dollar-store beach ball that escaped the “swim zone”, and he simply had to retrieve it. Wouldn’t you know the river in that area was roped off for a reason? Rip currents are a thing. I’m incredibly sad and also very, very angry, because it was such a stupid thing that was completely preventable. If someone (including the kid) had said “Oops, the beach ball is gone. Guess we’ll have another hot dog instead!” Jacob would still be alive. Fucking ridiculous.