Biologists often announce that a certain kind of animal has been found capable of using tools; this usually refers to something like using a stick to hunt for ants in a log, or a stone to crack nuts. But such announcements are completely unsurprising, since all animals use tools. Birds build nests, fish hide in the mud to escape predators, and squirrels use buildings as shortcuts between trees. If an animal executes its purpose by means of an external physical object, then that object can reasonably be regarded as a tool.
Which one of the following most accurately describes the role played in the argument by the claim that the biologists' announcements that a certain animal has been found capable of using tools are unsurprising?The claim that the announcements are unsurprising is what the argument is trying to establish. The support is that all animals use tools, given the argument’s broad definition of a tool as an external physical object used to achieve a purpose.
So the claim is the argument’s conclusion, not a premise.
(A) It provides evidence that the animals' activities given as examples are purposeful.
Wrong. The claim does not support the examples. The examples support the broader point that tool use is common.
(B) It is the conclusion of the argument.
Correct. The author argues that announcements of animal tool use are unsurprising because, under the broad definition given,
all animals use tools.
(C) It is an assumption used by the argument to justify acceptance of a broader conception of what a tool is than that usually accepted by the biologists.
Wrong. The broad conception of a tool supports the claim, not the other way around.
(D) It calls into question the basis of the biologists' conception of a tool.
Wrong. The argument does challenge the narrowness of the biologists’ idea, but the specific claim that the announcements are unsurprising is the conclusion drawn from that challenge.
(E) It addresses a weakness in the biologists' announcements that stems from their ambiguous use of the word "external."
Wrong. The argument does not focus on ambiguity in the word “external.”
Answer: (B)