The correct answer is foot-in-the-door phenomenon.
This means that if a person agrees to comply with a small favor, they are likely to do something more as well. So, these people will listen to the telemarketers' pitches, which means that they might even buy the product afterwards.
<span>recognize, document, and collect evidence at the scene of a crime. Solving the crime will depend on piecing together the evidence to form a picture of what happened at the crime scene.</span>