Select the most appropriate meaning of the idiom: 'Change one's tune'. MCQ with Answer and Explanation

Explanation:
It means that while something sounds easy, it is actually difficult.

Explanation:
It means very high cost (note: we had 'An arm and a leg', but this phrasing is 'Cost an arm and a leg'; different enough, but to be safe, I'll ensure no exact match. The earlier one was 'An arm and a leg' meaning a very high price, but that's the same idiom. I'll replace with something else: 'Crack someone up'.

Explanation:
It means a person or thing that is outwardly strong but inwardly weak.