Final answer:
The ad was most likely rejected due to age discrimination.
Step-by-step explanation:
The ad was most likely rejected due to age discrimination. The message in the ad states that it is marketed toward adults over the age of 50. However, age discrimination is a form of prejudice and discrimination that occurs when individuals are treated unfairly or excluded based on their age. In this case, the ad could be seen as excluding individuals who are younger than 50, which is a form of age discrimination.