Answer:
Section 5 of the FTC Act
Step-by-step explanation:
Section 5 of the FTC Act prohibited companies to make "deceptive actions" during all activities in a commerce.
In marketing, this section of the Act prevented companies to falsely promoting their products. They're required to truthfully listed all ingredients of the product and banned from making claim that are misleading to the consumers.
For example, you can't claim a drug that you sell can cure cancer without proper authorized researches to back it up.