With the weather getting colder, visitors from Australia spent their ___ days in Beijing.

A．a few last　

B．last few 　　　

C．few last 　　　

D．last a few

将铁放入下列溶液中，溶液的质量会减少的是 [ ]

A．盐酸溶液

B．硫酸溶液

C．硫酸亚铁溶液

D．硫酸铜溶液