Busy families like to buy plastic bags because they can______.

A．must give their students a better grasp of science and foreign culture
B．should seek to meet the challenge of greater global integration
C．need to adapt to the challenge of more advanced science
D．are fully qualified to serve our society

A．It dropped due to the weakness of the eurozone economies and the inexperience of the European Central Bank in dealing with the international markets.
B．People in most European countries refused to use euro instead of their own currency.
C．Counterfeiters made a lot of fake notes since people were not familiar with the new currency.
D．Some countries are not ready for the euro. They stopped using euro in daily purchasing.