ক. were we going
খ. are we going
গ. we are going
ঘ. we were going ✔
ব্যাখ্যা: Main Clause-টি Past Tense ('stopped us and asked us') হওয়ায় এবং Embedded Question হিসেবে 'where'-এর পর Assertive structure (Subject + Verb) বজায় থাকবে। সুতরাং 'we were going' সঠিক।