Answer:
Evaluation of alternatives
Step-by-step explanation:
Evaluation of alternatives is known to be a stage in the process of buyer decision whereby the consumer makes use of the information gathered during the information search in evaluating different alternatives brands present in the products category.
In this case, though,Robert has not reach a conclusion on the particular system he wants to buy, but he has narrowed it down to three based on the information he has gathered, this strictly shows that he is in an evaluation of alternatives stage of the buyer decision process.