Which of the following lists properly ranks the different environments from lowest to highest need to communicate with the customer?

a. Make-to-order, assemble-to-order, engineer-to-order

b. Engineer-to-order, make-to-order, assemble-to-order

c. Assemble-to-order, make-to-order, engineer-to-order

d. Assemble-to-order, engineer-to-order, make-to-order