The underlined part "this tiny human" in Paragraph 2 refers to（）

单项选择题What is pretty much settled according to Paul Sereno（）

A．Half of the dinosaurs lived alone.
B．Most dinosaurs moved long distances.
C．Many dinosaurs settled in the north.
D．Some dinosaurs lived in big groups.

单项选择题When Williams began working on his book, he （）.

A．was paid $ 35,000
B．learned to paint
C．had already buried the treasure
D．did not know what the story would be about