Which of the following statements is accurate regarding the implementation of modules in an ERP suite?

a$.$ A firm must install all modules simultaneously and cannot add functions incrementally.

b$.$ A firm has the flexibility to install modules incrementally, adding functions over time.

c$.$ A firm can only implement ERP modules in a predefined sequence determined by the vendor.

d$.$ A firm must install at least half of the available modules for the ERP suite to be effective.

e$.$ A firm is restricted to using only the modules that are compatible with its existing IT infrastructure.