Task: Question Answering
Input (English): Question: If logX/(a2 + ab + b2) = log Y/(b2 + bc + c2) = logZ/(c2 + ca + a2), then Xa - b.Yb - c. Zc - a =?

 Option A: 0

 Option B: -1

 Option C: 1

 Option D: 2

 Option E: 3
Output (English): Option C