Answer:
Option A, Acquisition
Explanation:
The first stage of learning is known as acquisition. It causes establishment of responses by pairing of Neutral stimulus, conditioning and un-conditioning stimulus. Once the association between a neutral stimulus and conditioned stimulus is established, the responses are acquired.
For example – If a bird is trained to pick a key whenever there is a sound of a bell, then after certain period of time an association will be established between the “ringing of bell” and “picking up of key” activity. Therefore, whenever the bird will hear the ringing sound it will search for key to be picked.
Thus, option A is correct.
I would go with 4 that's what makes the most sense to me, and i just learned about this last year so... I hope this helps good luck..