The first three options I see are all making-decision process to take action, but the last one is the one that is not like that. Researching is something that is not so close in meaning to what you need. That is why, D is a good option.
The conditioned stimulus was previously neutral stimulus that<span> triggers the same response in an organism </span><span> because it is associated with something else</span>
The conditioned stimulus in the situation in which the the child learns to wake up as soon as he/she has a sensation of a full bladder is the sensation of a full bladder.
