（）是笔迹签名的模拟，是一种包括防止源点或终点否认的认证技术。
参考答案：数字签名
Ad-makers choose words and brand names very carefully in order to make a creative image of the product they are ____.
A．processing
B．producing
C．providing
D．promoting
为什么说不能用塑料袋装热烫的食物？
