Denise works as a direct seller for Avon. She is determined to sell as many products to as many people as possible. Although she generally has a good relationship with customers, she has been known to be overly aggressive in trying to sell products. She often convinces consumers to purchase more expensive products even after they say they are not interested. As a result of Denise's high sales, she has become a top performer.

Recently, however, Denise's sponsor has been informed of complaints that customers have levied against Denise accusing her of "badgering" them into buying products. The sponsor meets with Denise and tells her it is unacceptable to pressure consumers into purchasing items they do not want.

Which variable of the marketing mix does this issue involve? Please explain.