Answer:
Ethos is credibility and reliability.
Explanation:
In an advertisement, the author could use ethos, pathos, and logos.
Ethos- What makes the source reliable? Is the author knowledgeable? Do they use facts? In an advertisement, the author often will use/mention a person who is connected to the topic to try to get you to do what they want.
Pathos- Pathos plays on your emotions and feeling to try and convince you to do what the author wants.
Logos- logos is logic and reason, the author will add facts to make their advertisement more convincing.