Why Is Repayment Under Chapter 13 Distinct from Other Types

Why is repayment under Chapter 13 distinct from other types of relief?

A) Because repayment plans are usually simpler and less expensive than Chapter 11 plans.
B) Because Chapter 13 is an option only for municipalities,not individuals and businesses.
C) Because Chapter 13 is the only type of relief available to debtors who are not insolvent.
D) Because repayment is voluntary only.A debtor cannot be forced into a repayment plan.
E) Because debts are discharged in Chapter 13 but not in other Chapters of bankruptcy.