我们用字母a表示一个有理数，试判断下列说法是否正确，若不正确，请举出反例。

（1）a一定表示正数，-a一定表示负数；

（2）如果a是零，那么-a就是负数；

（3）若-a是正数，则a一定为非正数。

While discussing the role of commodities as a vehicle for investment, a commentator makes the following statements : Statement 1 : During economic expansions, increasing supply tends to reduce the price of commodities. Statement 2: Investing in commodities can give the investor exposure to fluctuations in production and consumption. Are these two statements correct Statement 1 Statement 2（）①A. Incorrect Correct ②B. CorrectCorrect ③C. CorrectIncorrect

A. ①

B. ②

C. ③