The correct answer is B. Agesism is discrimination on the basis of age, most usually old age. This form of discrimination affects the elderly. In A. there is no instance of discrimination; in C., we see an instance of poverty (or at least reduced means), not discrimination. In D. we come close to an instance of discrimination; however, we are not told that he was pulled over because of his age, but rather because of his expired license plate tag (something that could happen to anyone regardless of age).
In B. we see an actual act of discrimination: Harry is refused a job because of concerns about his performance that are undoubtedly related to his age (speed is usually associated with youth, and slowness with old age).
