15. It is difficult to trace the history of certain ancient beads because they (A) are small in size (B) have been buried underground (C) have been moved from their original locations (D) are frequently lost

19. Which of the following statements best represents the type of "evolutionary fine - turning" mentioned in line1? (A) Different shapes of bills have evolved depending on the available food supply (B) White - wing crossbills have evolved from red crossbills (C) Newfoundland's conifers have evolved small cones (D) Several subspecies of crossbills have evolved from two species

15. It is difficult to trace the history of certain ancient beads because they (A) are small in size (B) have been buried underground (C) have been moved from their original locations (D) are frequently lost

其他試題

15. It is difficult to trace the history of certain ancient beads because they
(A) are small in size
(B) have been buried underground
(C) have been moved from their original locations
(D) are frequently lost