Secretary Leavitt stressed （） in the process of fighting H5N1 bird flu virus.

单项选择题What do many scientists worry about the disease ？（）

A．There is no effective way of treating it.
B．It may spread quickly among birds and poultry.
C．It may affect the world economy and politics.
D．It may change to an epidemic among human beings.

单项选择题Some European retailers warned that they would （）, if their stock isn't released soon.

A．close their stores
B．resort to legal action
C．take on a strike
D．take some violent actions