A hard-headed approach means a practical, realistic, and sensible way of dealing with something. The correct answer is this meaning because the expression is used figuratively, not only by its literal words.

Examples:

• The crisis needed a hard-headed approach, not emotional speeches.
• In an HSC essay, A hard-headed approach can express this meaning: a practical, realistic, and sensible way of dealing with something.
• When this expression appears in a passage, connect A hard-headed approach with the idea of a practical, realistic, and sensible way of dealing with something.