MGT$,$ Inc. works to build effective, long$-$term relationships with customers. It allocates a large budget to its call center so that customers know they can always be assisted with problems related to the company's products. In this way, MGT$,$ Inc. is attempting to gain a competitive advantage through

a$.$ quality.

b$.$ cost competitiveness.

c$.$ innovation

d$.$ speed

e$.$ service.