某商店橱窗内展示的衣服上标明“正在出售”，并且标示了价格，则“正在出售”的标示视为______。
参考答案：要约
He will come to understand your efforts sooner or later. It's just a matter of ________.[ ]
A. luck
B. value
C. time
D. fact
沟通
