Angela Markel says European Union could fail if Eurozone (欧元区)      over debt problems in Greece, Italy and other weaker economies.

A．pulls up

B．pulls down

C．breaks up

D．breaks down

家鸽卵细胞的营养成分主要在（　　）里．

A．胚盘

B．卵白

C．气室

D．卵黄