Answer: a. deceptive, and the FTC may issue a cease-and-desist order.
Step-by-step explanation:
A product that can increase human height by 6 inches sounds highly improbable and so is deceptive to people.
The Federal Trade Commission in it's role as a protector of Consumers from.unfair and deceitful practices in Commerce can act against Acme to stop them from deceiving the consumer.
One of the ways that the FTC can do this is by issuing a Cease and Desist order to Acme and if they fail to do so, can then take them to Court.