OG4 阅读 Q28

Choice B is the best answer. Lines 42-44("It acts... bloodstream.") provide evidence that antithrombin reduces compounds that lead to blood clots, as it acts as a "molecular bouncer, sidling up to clot-forming compounds and escorting them out of the bloodstream."
Choices A, C, and D do not provide evidence that antithrombin reduces compounds that lead to blood clots; these lines describe proteins, people unable to produce antithrombin, and the production of ATryn.