答案：B

题目分析：A. had been in已经在…    B. have gone to已经去了…，人没有回来     C. have been to已经去过，现在回来了，句意：玛利亚和康康在哪里？他们去英国了。故选B

点评：have gone to/ have been to的区别是中考英语中必须掌握的语言点，have gone to已经去了…，强调人去了某地还没有回来，have been to强调人已经去过某地，现在回来了，而have been in 强调呆在某个地方，为延续性动词。