Mentioning IIM Lucknow as your first choice is fine if you genuinely mean it, but avoid stating priority orderings because some panels use this to test honesty and it can backfire. The IIM L thread OP's interviewer asked what other calls he had and he answered honestly. A better response pattern: "I'm excited about IIM L's strong finance and general management placements, the Lucknow campus culture, and the alumni network in Delhi and Mumbai.
If I convert, I'd seriously consider joining." Never say "IIM L is my last choice" or "I'd pick IIM C over L" because it insults the panelists' institution. Never give a numeric priority list across IIMs (1=L, 2=K, 3=I).
Be diplomatically non-committal: "I'll evaluate all my calls based on placement fit, specialization, and overall experience." IIM Lucknow at Rs 22L fees and Rs 32.3 LPA average is genuinely a top institute; treating it as first choice if IIM ABC is unlikely is rational.
For candidates with IIM A, B, or C calls, be honest: "I have IIM C as another option and I'm weighing the fit carefully. Both are excellent institutions." Don't hide other calls; panelists can verify through the central system.
Panel reactions to honesty vary but usually respect candor over calculated answers. Practice this question because it's asked in 80%+ of IIM L interviews. Check your eligibility at collvera.