Option 1 -> Demure means modest, reserved, and respectful - the opposite of impertinent (rude/disrespectful).
Option 2 -> Indiscernible means unable to be perceived or distinguished clearly - unrelated to behavior or manners.
Option 3 -> Inconsistent means lacking consistency or being contradictory - not related to respectfulness.
Option 4 -> Incomprehensible means impossible to understand - unrelated to the concept of rudeness or respect.
Hence, Option 1: Demure -> Impertinent describes someone who is disrespectful or rude, while demure describes someone who is modest, reserved, and well-mannered, making them perfect antonyms -> correct