As long as the balcony doors remained（ ）, it wasn't that big of an issue.
A、closed
B、closing
C、to close
D、close
【正确答案】：A
【题目解析】：考点 Mordern English Grammar -voice and mood -passive voice -be-passive,get-passive and pseudo-passive 文字解析 本句意为只要阳台门关着，就不是什么大事。门只能被关，所以使用被动语态。
