Agamex. Inc, an established feedlot-supply company, has a beta of 1.25, and a payout ratio of 70%. The risk-less rate is 4% and the expected return on the market is9%. What is the appropriate leading price-earnings ratio to be used in the valuation of this company if an analyst expects a long-term dividend growth rate of 4%（）

A. 4.80.

B. 6.22.

C. 11.20.

哪项不是21-三体综合征的特点（）

A.免疫功能低下

B.白血病的发生率较低

C.性发育延迟

D.智力低下

E.喂养困难