It's some change in the conditions around the organism, which the organism can detect and respond to. A change in temperature, more light, or something physically poking the organism are examples.
        
             
        
        
        
<span>Based on a study of recreational drugs that have been linked with a higher incidence of sudden infant death syndrome was the use of Marijuana and other recreational drugs like cocaine, crack, crystal, amphetamine, methamphetamine, and speed but cocaine was the most commonly used drug. The basis of the infant sudden death was that both maternal and paternal were using at the time of conception and during in the latter stage of pregnancy. Tobacco smoking of the mother during pregnancy can also affect the life of the baby. There is statistics base on the study on how many percents it will affect the condition of the infant.</span>
        
             
        
        
        
Answer:
False humans can be classically conditioned.
Although humans learning something wouldn't general be considered classical conditioning but rather Cognition. That doesn’t mean they can’t “learn” via classical conditioning.