______ how the splendid Maya Culture disappeared all of a sudden

______ how the splendid Maya Culture disappeared all of a sudden from the earth,it remains a mystery hard to solve.
A、In turn
B、As to
C、Thanks to
D、As a rule
【正确答案】：B
【题目解析】：as to 就…而论，至于；In turn 轮流；Thanks to 多亏于；As a rule 通常，一般来说句意：至于辉煌的玛雅文化是如何突然从地球上消失的，这仍然是一个难以解开的谜。B符合题意