【单选题】

The title of the talk is (11)____________.He wants to deal with (12) ____________and (13)____________first.In the future;(14) ____________can operate at almost two thousand miles per hour.We’’ll have (15)____________, or hovercraft in the (16) ____________and (17)____________ class.

A、noisy
B．poor efficiency
C．poor control
D．All the items above.