The correct answer would be (D) Blue jays and finches nest in the same oak trees.
Competition is a type of ecological relationship between the organisms of the same or different species in which they compete for the same resources.
Limitation of any one resource used by both the organisms would become the limiting factor.
For example, blue jays and finches depend on the same oak tree for their nesting. Thus, limitation or decrease in the number of oak trees can become the limiting factor.
Answer: a tiny muscle connected to each hair follicle and the skin. When it contracts it causes the hair to stand erect, and a "goosebump" forms on the skin.
