TOEFL Listening: TPO-TOEFL阅读TPO - 163QF036CD16QLW4N$

All of the following are mentioned in paragraph 4 as reasons why it is difficult to determine whether translocations have been successful EXCEPT: A. Translocations sometimes occur for reasons other than conservation. B. Failures are not necessarily reported. C. Adequate monitoring is sometimes impossible. D. There is no widely agreed on definition of success in translocations.