OG1 阅读 Q29

Choice A is the best answer. The authors state: "We believe that the bases will be present almost entirely in their most probable forms. If this is true, the conditions for forming hydrogen bonds are more restrictive, and the only pairs of bases possible are: adenine with thymine, and guanine with cytosine" (lines 31-35"We...cytosine"). The table shows that the pairs adenine/thymine and guanine/cytosine have notably similar percentages in DNA for all organisms listed.
Choice B is incorrect. Although the choice of "Yes" is correct, the explana-tion for that choice misrepresents the data in the table. Choices C and D are incorrect because the table does support the authors' proposed pairing of nitrogenous bases in DNA molecules.