Which word describes highly favorable and admirable qualities?

The term that best describes highly favorable and admirable qualities is "epitome." When you refer to someone or something as the epitome of a certain quality, you are indicating that it represents the highest standard or a perfect example of that quality. This word implies an ideal model, showcasing characteristics that are widely regarded as admirable, making it suitable for capturing the essence of exceptionally positive attributes.

The other options, while they may hold relevance in certain contexts, do not convey the same meaning. "Callow" refers to someone who is inexperienced or immature, thus lacking admirable qualities. "Benevolent" describes a disposition characterized by kindness and a desire to help others, which is positive but doesn't cover the broad spectrum of favorable attributes. "Ex officio" refers to a position held by virtue of one's office or role, and does not connote the qualities themselves. Therefore, "epitome" stands out as the word that encapsulates the notion of exemplary and commendable characteristics.