💡 Detailed Explanation
The suffix '性' (-sei) is added to a noun to mean 'nature,' 'property,' or '-ity.' '実用性' (jitsuyousei) means 'practicality' or 'utility.' '化' (-ka) means '-ization' (e.g., 映画化 - film adaptation). '的' (-teki) makes a noun into an adjectival noun, meaning '-like' or 'related to' (e.g., 実用的 - practical). '風' (-fuu) means '-style' or '-like' (e.g., 和風 - Japanese style). The sentence requires a noun meaning 'the quality of being practical'.