Answer :
You should A. use it to remember a word. This moves it from the short term memory to the long term, where you can recall it when needed
Three out of the four ways, you won't be able to remember a new word well with, but if you keep using a new word in the right situation, you start to get accustomed to the word, and if you get accustomed to it, you start to maintain the word in your vocabulary, so, the best answer is A. use