A：Seating; wa
B：Seated; were
C：Sitting; wa
D：Sat; were
“火树银花不夜天”在喜庆的盛大节日里，人们常常要燃放礼花爆竹，此时旁观者最好张口，或闭嘴、堵耳。这种做法主要是为了（ ）
— Can I come in?
— （ ）
