A means to an end means something done only to achieve a larger purpose. The correct answer is this meaning because the expression is used figuratively, not only by its literal words.

Examples:

• For him, the part-time job was a means to an end.
• In an HSC essay, A means to an end can express this meaning: something done only to achieve a larger purpose.
• When this expression appears in a passage, connect A means to an end with the idea of something done only to achieve a larger purpose.