Aishah, a resident of lower manhattan, suffers from ptsd after witnessing the attack on the twin towers of the world trade center on september 11, 2001. a certain acrid burning smell can trigger intense feelings of jitteriness and distress for her. this is an example of:

classical conditioning                              

Explanation:

Classical conditioning: In psychology, the term classical conditioning is a form of learning in which a conditioned stimulus or CS gets connected or associated with an unconnected unconditioned stimulus or the US to give rise to a behavioral response named as conditioned response or CR. The CR over here is considered as the learned response which was a neutral stimulus earlier.

The classical conditioning works with involuntary responses.

In the question above, the given statement is an example of classical conditioning.

The statment is an example of classical conditioning        

Explanation:

d. the polar jet stream   lies between the polar easterlies and trade winds should be your answer