Final answer:
Mr. Rioja's explanation is an example of rationalization, a defense mechanism in which a person provides a self-serving but incorrect or illogical explanation for their behavior or beliefs.
Step-by-step explanation:
Mr. Rioja's explanation is an example of rationalization. Rationalization is a defense mechanism in which a person provides a self-serving but incorrect or illogical explanation for their behavior or beliefs. In this case, Mr. Rioja justifies his refusal to help his son financially by stating that it would hinder his son's development into an independent adult. However, this explanation is not based on sound reasoning or evidence.