TOEFL Listening: TPO-TOEFL阅读TPO - M4CE2I54GRGNAL0FN$

Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. A. The limited number of colonies was not due to the distribution or availability of potential nesting sites. B. There was no lack of suitable trees or potential nesting sites in the study area. C. The number of nests was directly related to the number or the distribution of suitable trees. D. Neither the number nor the distribution of colonies could be explained by the availability of suitable nest sites.