Although I do not have Sharon Kaye's text, hopefully the following texts may suggest why the fourth option is most likely not what Dewey would consider a tool to be.
Elizabeth Anderson writes the following about John Dewey's ethics:
Value judgments are tools for satisfactorily redirecting conduct when habits fail. As tools, they can be evaluated instrumentally. We test our value judgments by putting them into practice and seeing whether the results are satisfactory — whether they solve our problems with acceptable side-effects, whether they enable successful responses to novel problems, whether living in accordance with alternative value judgments yields more satisfactory results.
Although the above quote is about value judgments, the emphasis placed on them as "tools" for Dewey emphasizes his "instrumentalism" which Richard Field describes as follows.
Unlike traditional approaches in the theory of knowledge, which saw thought as a subjective primitive out of which knowledge was composed, Dewey's approach understood thought genetically, as the product of the interaction between organism and environment, and knowledge as having practical instrumentality in the guidance and control of that interaction. Thus Dewey adopted the term "instrumentalism" as a descriptive appellation for his new approach.
The question provides four options. One of them is least likely to be a tool for a pragmatist, instrumentalist such as Dewey. Only one of them would not likely be something we could use to "test our value judgments", to "solve our problems with acceptable side-effects" or to allow us "interaction between organism and environment".
The beaver dam may be a tool for beavers, but of the four it would seem to provide the least instrumental value for humans. The other three, universities, computers and apartment buildings, would provide more opportunity for interaction (at least from a human perspective) between organism and environment.
Anderson, Elizabeth, "Dewey's Moral Philosophy", The Stanford Encyclopedia of Philosophy (Fall 2018 Edition), Edward N. Zalta (ed.), URL = https://plato.stanford.edu/archives/fall2018/entries/dewey-moral/.
Field, Richard, "John Dewey (1859—1952)", Internet Encyclopedia of Philosophy https://www.iep.utm.edu/dewey/