I voted "other" for several reasons.
#1: If you are shooting in a legal-to-shoot location, you're not legally bound to disarm, but it might be best if you do....out of mere respect, and to display that you are a law-abiding person.
#2: I don't think that anyone would even THINK of running toward a LEO while openly armed! That would definitely pose a threat to the LEO!
#3: "Communication"! As you make your approach toward the LEO, why not "talk it up", and articulate that you're merely "plinking" at targets or rodents. Also, explain that you are either NOT armed, or that you have a holstered weapon! If the LEO "instructs" you to stop and disarm, then DO SO!
At that moment, the LEO is the "authority", much like a rangemaster at a formal shooting range.
#4: In the scenario that you presented, YOU don't know WHY that LEO responded to your shooting location. If some sort of rabid anti-gun person called in and said that you were shooting at people in the sand pit, then you're a "suspect", since the LEO has not been able to verify if you're a "good guy" or a mass murderer!
#5: Nation-wide, there's one LEO per every 10,000 or so citizens. I'm not trying to bring up the "us against them" thing, but....the "Thin Blue Line" is a matter-of-fact! By displaying yourself as an honest, law-abiding, responsible and respectful person, by disarming when "instructed" to do so, the contact with a LEO will, most likely, end up being a "positive" event....and might even turn out to be a very short contact, instead of a lengthy "investigation".
Hey, my one-and-only traffic ticket that I have gotten was when I was 17 years old (I'm almost 60 years old now). The officer was professional, and I was definitely respectful toward him. I deserved the ticket! That contact with the officer was a "positive" event, as well as a "learning" lesson. For what it's worth, 7 years after getting that ticket, I ended up being that same officer's PARTNER when I was a rookie! He didn't recognize me, and I didn't expect him to, for the police have countless contacts with the public. We both had a good laugh about that ticket! I learned a LOT about "professionalism" from him, starting with the way he treated me when I was only 17 years old!