Answer:
A. the chemical triggers a fixed action pattern
Explanation:
Konrad Lorenz, who is the founder of the fixed action pattern, described it as an instinctive behavioral sequence that is highly stereotyped and species-characteristic. Fixed action patterns are said to be produced by the innate releasing mechanism, a "hard-wired" neural network, in response to a sign stimulus or releaser. Once released, a fixed action pattern runs to completion.
Fixed action patterns have been observed in many species, but most notably in fish and birds
Fixed action patterns have been shown to be evolutionarily advantageous as they increase both fitness and speed. However, as a result of their predictability, they may also be used as a means of exploitation. An example of this exploitation would be brood parasitism.
