Is the element of the promotion mix that involves direct interaction between a company representative and a customer.

Personal  selling

Explanation: In personal selling the sales force personnel of an entity tries to sell the product to the customer after a face to face interaction.

Individuals in the sales force tries to persuade the customer to buy or at least try the product for once, they do so by the specialized knowledge for the product or by the appearance or attitude.

Thus, from the above explanation we can conclude that, personal selling is the right answer.

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