The Mechanism by Which a Crayfish Decides Whether to Approach

The mechanism by which a crayfish decides whether to approach or withdraw from illumination appears to be

A) Mutual inhibition of sustaining neurons.
B) Complex interconnections in the visual cortex.
C) Whether or not sustaining neurons are activated.
D) Motor neurons that propel the legs either forward or backward.
E) a switch neuron in the caudal ganglion.