A rising tide lifts all boats means a general improvement that benefits everyone. 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: A rising tide lifts all boats can refer to a general improvement that benefits everyone.
• Story example: A writer may use A rising tide lifts all boats when describing a general improvement that benefits everyone.
• Exam example: When a sentence contains A rising tide lifts all boats, choose the meaning “a general improvement that benefits everyone.”