Last but not least means last in order but still important. This answer is correct because the expression has a fixed figurative meaning in English. In an SSC idiom question, students should match the whole phrase with its accepted meaning rather than translate each word separately.

• Classroom example: Last but not least can refer to a situation involving last in order but still important.
• Story example: A writer may use Last but not least when describing a situation involving last in order but still important.
• Exam example: When a sentence contains Last but not least, choose the meaning “last in order but still important.”