Global warming. Not reversing it, because that would most likely cause an ice age, but keeping it under control.
The correct answer to the question stated above is the first option: <span>an instinctive behavior was tied to a different stimulus.
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Pavlov's experiment was a typical case of classical conditioning because an instinctive behavior was tied to a different stimulus.
The answer is definitely "D"
half of two threadlike strands of replicated chromosomes
