In this lesson I notice that all “word bank” exercises offer exactly one month name to choose. So you need not know which month is which, you simply choose the only month name available. Wouldn't it be better to offer at least two months?
We cannot influence the word bank choices in any way. That is controlled by Duolingo programs automatically.
Personally, I consider all word bank exercises simply too simple and now with crowns I never do lesson exercises, only test-outs.