The correct answer is A. unsympathetic.
A humane person is one who is kind and compassionate, especially towards those who are suffering. A police officer who is known to be humane in his approach is likely to be understanding and patient, even in difficult situations. He is also likely to be respectful of the rights of others, even when they are breaking the law.
The other options are incorrect because they do not describe a humane person. A person who is unsympathetic is not kind or compassionate. A person who is uncultured is not familiar with or interested in the arts and humanities. A person who is uncompromising is not willing to change his or her mind, even when presented with new information. A person who is uncivilised is not polite or respectful.