题目

Grandparents are respected in many human societies. But telling stories about old times and overfeeding grandchildren seem like human qualities. Are these classic grandparent behaviors really limited to humans？Do any animals know their grandparents the way people do?For most species on Earth，the answer is certainly “No”. Usually，there aren't grandparents around anymore when an animal is born，said Mirkka Lahdenpera，a biologist at the University of Turku in Finland. Even if an animal's life span does overlap（重叠）with its grandparents'，most species spread out to avoid compe温室栽培胡萝卜，采用什么颜色的玻璃做顶棚更能提高产量A. 红色 B. 蓝紫色 C. 绿色 D. 无色