All of the following are useful for encouraging a prospect's participation in the presentation EXCEPT:

A) product use.
B) visuals.
C) questions.
D) demonstrations.
E) premiums.

Premiums

The additional amount paid for a commodity or service above its basic cost, often associated with insurance policies or enhanced product features.

Prospect's Participation

The involvement or engagement of a potential customer in the sales process, often through interaction or providing feedback.

Product Use

Refers to the manner in which a product is utilized by the consumer, often determining its effectiveness, functionality, and satisfaction derived from it.