If I was the interviewer, I would consider a simple calculated answer to be wrong. I would hope the candidate asks for more information, or mentions capacitor resonance, or says a few words about parasitic inductance, or at least explains what assumptions he used when making the calculation. That would demonstrate experience with practical design issues.
Some interviewers ask questions carefully worded to test the candidate's education, experience, problem-solving ability, motivation, etc. Such questions may not have a right or wrong answer, but are intended to initiate a thoughtful discussion.