Multiple Choice$0\mathrm{.}4$ points$16.$ Which of the following is NOT an important implication of reference groups for marketersa. Reference groups serve as information sources and influence perceptionsb. Reference groups affect an individual's aspiration levelsc. Reference groups create product trends that always align with consumer behaviord. Reference groups' norms either constrain or stimulate consumer behaviore. Reference groups influence the clothes people wear and the cars they drive