Various Ioun Stones include the following bit in their description:
(…) Thereafter, another creature must use an action to grasp or net the stone to separate it from you, either by making a successful attack roll against AC 24 or a successful DC 24 Dexterity (Acrobatics) check. You can use an action to seize and stow the stone, ending its effect. (…)
Notably, a creature trying to grasp or net the Ioun Stone must use their action to make an attack roll. But what kind of attack roll is this?
Can it use a weapon? Is it melee or ranged? Do you add Dexterity or Strength (or neither) to the attack roll? Are you proficient in this attack?
What are the options for a character when they are required to “make an attack roll”?