单项选择 1.It is reported that people throw ( )plastic bags alon

单项选择 1.It is reported that people throw ( )plastic bags along this street every day.
A.hundred B.hundreds C.hundred of D.hundreds of
2.Some scientists think that it will take ( )of years to make robots do most work for humans.
A.hundreds B.hundred C.thousand
3.Good news!About three ( ) students can go to Yangzhou Middle School for further studay.
A.hundred B.hundreds C.hundreds of D.hundred of