
A.在B期间,蜘蛛数量减少的原因是该种蜘蛛的食物不足 |
B.在A期间喷洒针对害虫I的农药,蜘蛛数量将增加的更快 |
C.在C期间两种生物的数量基本保持不变,这是因为两者之间已不存在食物关系 |
D.引入蜘蛛防治害虫,是生物防治的实例,说明外来物种入侵对环境的影响不大 |

同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

