Correct option is B
The correct one-word substitute for the given group of words is "Actionable."
Explanation: "Actionable" refers to something that gives grounds for a legal action or lawsuit.
Example: "The defamatory statements made by the journalist were considered actionable."
Meanings of all options:
· Lawful: Conforming to, permitted by, or recognized by law or rules.
· Actionable: Giving cause for legal action.
· Legalizing: To make something legal or lawful.
· Objectionable: Arousing distaste or opposition; unpleasant or offensive.