【单选题】

Which of the following statements about the individual gustatory neuron is true, based on information provided by the passage
A．(A) It creates a neurological signal only when it comes into contact with its primary tastant.

B．(B) Its function is not to identify tastes, but to identify similarities and differences between them.
C．(C) Its primary importance is in distinguishing between the various qualities of a mixed stimulus.
D．(D) It provides roughly equivalent signals when in contact with a major stimulus and a minor one.
E．(E) It plays a fairly minor role in the across-pattern theory, compared to the labeled-line theory.