In which case is someone being a consumer? A. Ibrahim is driving the car he just bought.
B. Erin is thinking about writing a book.
C. Chris is looking up at the stars in the sky.
D. All of the above

The controlled use of fire by hominids: (a) limited the expansion of hominids into certain environments, such as dry grasslands. (b) decreased the amount of food energy available in the hominid diet. (c) contributed to geographical expansion and food production techniques in positive ways. (d) has been shown to contribute little to the digestive process of hominids.