单项选择题
W: Great. That means 25 people will come so far. But how many of them are kids M: About 15 kids are coming, and 6 of them are close to your age.
A.6. B.10. C.15. D.25.
A. put asideB. give upC. deal withD. take up
A. having a DNA-test of a young leaf of the treeB. mixing different types of suitable genesC. checking its young branches before plantingD. comparing the shining lines with the genetic signs