We saw AN otter.
You use ‘an’ when the next word starts with a vowel.
For example:
With vowel - There was AN eagle.
Not a vowel - There was A bird.
I think the correct answer from the choices listed above is option B. The element that should be placed on the backside of a word card is the pronunciation of the word. This should be more helpful to the one you are teaching because you will know the right pronunciation of the word.
Answer:
D. "The James Madison Memorial Building", replied the docent, "houses the Folger Shakespeare Library".
B. Reveal insight into the husband’s character