Explanation:

- A black sheep is someone who is considered the odd one out or disgraceful within a group, usually a family. They don't fit in or are seen as a troublemaker.

- Option 1: *An unlucky person* - This implies someone who frequently experiences misfortune. While they might be seen as unfortunate, they aren't necessarily disliked.

- Option 2: *A dangerous person* - Suggests someone posing a threat; however, the idiom isn't about danger.

- Option 3: *A cunning person* - Refers to someone who's sly or crafty, which doesn't align with the idiom's meaning.

- Option 4: A disfavoured person - ?? This best captures the meaning of "a black sheep," as it relates to being excluded or frowned upon in social contexts.