💡 Detailed Explanation
The verb 'あやまる' (謝る) means to apologize when one does something wrong or makes a mistake. Option 2 is correct: 'If you end up doing something bad, you must apologize to the other person immediately.' Option 1 is incorrect because you apologize for your own mistakes, not a friend's homework. Option 3 is incorrect because asking for directions at a police box uses '尋ねる' (tazuneru) or '聞く' (kiku), not '謝る'. Option 4 is incorrect because asking whether someone will participate in a party uses '決める' (kimeru) or '教えて' (oshiete), not '謝る'.