I heard the same thing at normal speed. After I got the wrong answer I replayed it, heard it again, then played the slow speed. It only sounded like "les" when slowed down. :/
I thought because French required an article, the "la" could be there just for grammatical reasons and it was basically ambiguous in English, so we could say either "carrot" or "the carrot" -- seems like this worked with other words along the way. But "carrot" was marked wrong...