Table 3.

Students’ errors while solving multiple-choice biology problems

Problem-solving errors	Description: this category refers to parts of the written think-aloud in which the student …	Example quotes
Domain-general errors
Contradicting	Stated two ideas that were in opposition to each other.	(C) says that are they same based on the biological species concept. The data that proves there are hybrids proves this to be true. I mark it.
		(E) could also make sense but I think there is enough information to make a decision.
Disregarding Evidence	Did not use some or all of the data provided in the problem.	A. Incorrect answer—the data does not represent morphological characteristics, so cannot conclude this answer. Move on.
Misreading	Read the question prompt or answer options incorrectly	B is incorrect because Atlantic eels should show some resistance since the Atlantic eel have developed in the presence of krait toxin.
Opinion-Based Judgment	Gave an opinion and did not use biology content knowledge.	E may be right, but I feel confident with C.
Domain-specific errors
Making Incorrect Assumptions	Stated that the graph or other visual representation provides no useful information.	Examine graph.
		Hybrids are not seeming to live (not viable).
Misunderstanding Content	Showed incorrect understanding of content knowledge.	(C) says that are they same based on the biological species concept. The data that proves there are hybrids proves this to be true. I mark it.

The errors are presented in alphabetical order, described, and illustrated with example quotes from different students’ documentation of their solutions to the problem shown in Figure 1 (except for Misreading, which is from problem 13 in Supplemental Figure S1).