Sizzlin$$ Shine is a company that uses trained detailing professionals to apply wax to automobiles by hand and uses mechanical polishing equipment. To maintain Sizzlin$$ Shine$$s quality image, the owner provides complete training for each employee in company operations, objectives, and performance standards. What unique aspect of services is the owner attempting to address?

a$.$ heterogeneity

b$.$ intangibility

c$.$ inseparability

d$.$ perishability