Answer: 2) rule of reciprocity
Step-by-step explanation:
The rule of reciprocity is also known as the rule of pay back. It describes the favour done to an individual when they buy a product. More like paying back a favour done to an individual for patronizing a product.
The Real estate company is using the rule of reciprocity persuasion technique to convince their clients to come for the short sales promotion meeting. In most cases, this method of sales persuasion technique works, as clients would always want something extra than what they are buying.