31. 若 A2, B2, C2 之鍵能分別如下：(A - A) = 420 kJ/mol(B - B) = 600 kJ/mol(C - C) = 650 kJ/mol關於分子振動頻率(vibrational frequencies) 的高低排序應為
(A) A2 = B2 = C2
(B) A2 > B2 > C2
(C) A2 < B2 < C2
(D) A2 < B2 = C2