Answer:
The answer is: "habilidad"
Step-by-step explanation:
"Habilidad" means skill, and we know it's a femenine word as it has "a", it should be a femenine noun because it needs to follo "la" as it says in the summary. So basically it'll be: and needs to be practiced and examined the selection of words and the skills in the way of using words in an efficient manner.