Refer to the Scenario Below to Answer the Following Questions

Refer to the scenario below to answer the following questions.
Reliable Tool Company is a manufacturer of hubs and axles for the trailer and heavy truck industry. Although Reliable Tool only has fifteen customers, the company is the sole supplier of hub and axle components to those customers. Monthly sales at Reliable Tool are approximately $1 million. "You might say we have all of our eggs in one basket," says owner Arthur Deetz. Therefore, it is critical that a competent sales force nurture those few but large accounts. Ninety-five percent of Reliable Tool's customers are located in Michigan, Ohio, and Indiana, which means that travel time to all customers is relatively short. However, given the nature of the industry, time spent with each customer is essential.
-Which type of direct marketing would make the most sense for Reliable Tool to use to supplement personal selling, considering that the company has only a few customers but very deep lines of complex products?

A) life cycle marketing
B) DRTV
C) infomercials
D) catalogs
E) email blasting