After an answer has been filed, can the plaintiff amend his complaint by changing entirely the nature of the action?

• A. NO. Amendments cannot alter the nature of the action.
• B. YES, amendments may substantially alter the nature of the cause of action.
• C. YES, but only if the substantial change serves substantial justice.
• D. Yes, the current rules allow amendments that substantially alter the nature of the cause of action, provided the change serves substantial justice and prevents delay.

Answer: (D)