Which of the following is NOT a source of adverse effects of inflation on an economy Inflation: （）

A. distorts the information delivered by prices.

B. affects product prices without changing underlying resource prices, such as wages, in the long run.

C. increases the uncertainty accompanying investment and other activities involving future payments.

在重金属的检查中，加入硫代乙酰胺试液作为(　　)

A．标准溶液
B．显色剂
C．pH调整剂
D．掩蔽剂
E．稳定剂