A is Correct. Assumptions are a sure path to a problem or misunderstanding, especially when based on very little or unfounded information, or bias. Perhaps Margarita let her sentimental feelings about her grandmother and desire to form a connection with Alberto cloud her best judgment and ability to manage any deeply held bias toward others.
C is Correct. Generalized statements are similar to stereotypes and can often be offensive and lead to prejudice. Often such statements arise from implicit bias. See each person as an individual and appreciate them for who they are.
B: Incorrect. When someone has given honest and respectful feedback, telling them to not be “so reactive” would only make matters worse.
D: Incorrect. Rather than defending her assumption, a simple apology would serve better.