Answer:
The answer is Lead generation.
Explanation:
According to the hubspot.com, "Lead generation is the process of attracting and converting strangers and prospects into someone who has indicated interest in your company's product or service".
From the text, we see that the company, Laelle Inc. tried to attract potential customers by handing them pamphlets containing their contact details. In the definition, we see that lead generation works with prospects who have indicated interests in the particular product or service offered.
When these firms go through the pamphlets and see that they need the service Laelle Inc. is offering, they will immediately contact them.
In this case, the lead generation was initiated by identifying the prospects and sending them pamphlets bearing contact details and sealed when the prospects place that call across indicating interest.