Mafia 101. Disputed Island

If your answer to the second question is correct, Uranus, and mine to the third (I have no doubt about the latter, except perhaps in the nuances of the wording), then the first question must relate to either status or weaponry. Weaponry hardly plays a role in terms of observation skills... Status? Perhaps it does. Locals might be more observant (although the old woman isn't local, technically...), and those who are physically and mentally healthy also have certain advantages. Or not? In any case, it's amusing that there are so few options, yet it's not easy to choose clearly.