A：
B：
C：
D：
— Ang Lee, a Chinese director, won the Best Director again in his last year.
— How great he was! It was his time to win an Oscar.
下列各组物质中，相互间一定互为同系物的是（ ）
①∀x∈R，f（x）＜0或g（x）＜0；
②∃x∈（﹣∞，﹣4），f（x）g（x）＜0．
则m的取值范围是____．
