I supposed that it is possibly that what Coventina presented were so distorted or abstract that the student didn't recognize the examples as human. Or maybe the examples were visibly obviously male or female, and the student was afraid of the consequences of pointing out those facts.
It's more likely, sadly, that the college student is lazy, unmotivated, and nearly illiterate (i.e. (s)he thought Fun With Dick and Jane was a porno with Spot and Puff doing bestiality).