Nadia may be able to repeat the last few words that someone spoke, even if she wasn't really paying attention. this is because the information is still available in her memory.

The question is asking for some kind of memory, so let's think what kinds of memory are there?

One way to divide memory is into long-term and short-term, and short-term memory describes a small number of recently perceived items. Short term memory is the correct answer here- and if she does not rehearse those words, they won't be passed to her long-term memory.