問題詳情：
According to Global Blue, a tax-free shopping consultancy, Chinese shoppers were said to be the biggest overseas spenders in the year 2013, each customer ________ an average of ￡1,367 per transaction.
A. spent B. to spend C. spending D. has spent
【回答】
C
知識點：動詞時態與語態
題型：選擇題
