The _________ (frighten) thing is the rate at which it is increasing.

A．The fish and the bird stared at Mao Qiang and Li Ji for a long time.
B．The fish and the bird cried out in admiration of Mao Qiang and Li Ji.
C．The fish and the bird didn’t consider Mao Qiang and Li Ji to be beautiful.
D．The fish and the bird thought Mao Qiang and Li Ji were the most beautiful ladies in the world.