The answer would be "available" or option C. Jarrod had no AVAILABLE proof that his little sister hid his car keys, but he couldn't think of anyone else who would have put them in the dog's bowl. Accessible could mean available for example: The armory is accessible to any person that is within the colony. Meaning that to any person that is in their colony has access to the weapons or in this case the armory is AVAILABLE to anyone who is in their colony.
Hope this helps!
