【正确答案】 A

【答案解析】[试题分析] 副词辨析题。
[详细解答] frequently adv．常常，频繁地；incidentally adv．附带地，顺便提及；deliberately adv.．故意地；eventually adv．最后，终于。显然，此处选用frequently符合题意，故答案为A。