Answer:
d. classify firms according to their number of customers
Step-by-step explanation:
Since Dion wants to market his services to these car firms, he should consult for data that can be used to classify firms according to the customers that they have.
It has been stated clearly that people have to drive to Lubbock dallas, or Austin to get their cars serviced, so the firms can beclassified according to the number of customers.