Correct Answer: Civilised

Solution : The fourth option is correct.

Explanation : We have to find a word that contrasts with the primitive or uncivilised nature of barbaric . Civilised is the suitable antonym, as it denotes a state of advanced social and cultural development, opposite to the barbaric or uncivilised state.

Therefore, the correct antonym is civilised.

The meanings of the other options are as follows:

1. Indifferent : This word means unconcerned or apathetic.
2. Brutal : The cruel or savage behaviour.
3. Inquisitive : This term refers to being curious or eager to learn.