The first time a bird builds a nest, the bird builds the nest perfectly. This kind of behavior is an example of

A. instinct.
B. trial-and-error learning.
C. imprinting.
D. conditioning.

The correct answer is A. instinct.

Instinct refers to a natural behavior that is innate and does not require prior learning or experience. When a bird builds its first nest and does so perfectly without any trial-and-error or learning process, it demonstrates instinctive behavior.

To arrive at this answer, you can apply the process of elimination by understanding the definitions of each option:

B. Trial-and-error learning: This involves learning through repeated attempts and adjusting behavior based on the outcomes. Since the bird builds the nest perfectly the first time, trial-and-error learning is not necessary.

C. Imprinting: Imprinting is a process during a critical period where animals form strong attachments to the first object they encounter, usually their parents. This behavior is not relevant to the bird building a nest.

D. Conditioning: Conditioning involves learning by associating a stimulus with a response. In the case of the bird building a nest, there is no stimulus or specific response being conditioned.

By considering the definitions and eliminating the incorrect options, you can conclude that the bird's behavior is an example of instinct (option A).