To be a/an （） is the ambition most appropriate for those who see the world as being in constant change, and who, without thinking that they can control it, wish to influence its direction.

单项选择题It is developing a service that will let you create all online identity that can （）various claims that it will back up.

A. plunge
B. assert
C. exert
D. insert

单项选择题Business travelers may grumble about moving to the back of the Airbus, but in the air and on the ground, special deals （） for those who are willing to lower their sights.

A. abound
B. indulge
C. permeate
D. revive