試題詳解

73. The phenomenon of fusion is likely to occur when, after a period of geographic isolation, two populations meet again and ______.
(A) an increasing number of viable, fertile hybrids is produced over the course of the next one hundred generations
(B) an increasing number of infertile hybrids is produced over the course of the next one hundred generations
(C) no reproduction occurs in the hybrid zone
(D) a decreasing number of viable, fertile hybrids is produced over the course of the next one hundred generations
(E) fewer and fewer hybridization occurs