单选题回答题：


The second paragraph implies that

A．the world’s earthquake laboratories Were not effective in detecting seismic“pie-shocks”．   
B．seismic signaling Was the major communication form of many animal species．
C．those animal species can feel and understand all kinds of vibrations．
D．all strange animal bellaviors Can be explained by extra-sensory perception．

A．relating to terrestrial vibrations．   
B．connecting to lab researches．   
C．centering on human．beings．
D．focusing on animal behaviors．

A．biologists have properly realized  the conllllon existence of seismic signaling.
B．seismic signaling is a means of communication that has been comprehensively studied.
C．seismic signaling call show many mysterious featums of animal behavior.
D．the research approach has led to the fruitful research into seismic signaling.