Questions: consists of all the techniques sellers use to persuade consumers to buy their goods and services.

The answer is C: Promotion.

Explanation for each option:

• Closing: This refers to the final step in the sales process where the seller finalizes the sale and the buyer agrees to purchase the product or service. It is not a broad category of techniques used to persuade consumers but rather a specific stage in the sales process.

• Preselling: This involves activities that prepare potential customers for a sale, such as providing information or creating awareness before the actual sales process begins. While it is a technique used to influence consumers, it is not as comprehensive as the term "promotion."

• Promotion: This encompasses all the techniques and strategies that sellers use to persuade consumers to buy their goods and services. It includes advertising, sales promotions, public relations, and personal selling. Therefore, it is the most appropriate term for the question.

• Advertising: This is a specific form of promotion that involves paid, non-personal communication through various media to inform or persuade an audience. While it is a technique used to persuade consumers, it is just one component of the broader category of promotion.