Explanation:

- In civil procedure, a decree is a formal adjudication which conclusively determines the rights of parties with regard to all or any of the matters in controversy.

- An order is any formal expression of a decision of a civil court which is not a decree.

- Every decree is appealable unless otherwise expressly provided.

- Every order is not appealable; only certain orders listed under the Civil Procedure Code (Section 104 and Order 43 Rule 1 CPC) are appealable.

- Both decree and order can be appealable, but not every order is.

Option 1: Decree

Option 2: Order

Option 3: Both (a) and (b)

Option 4: Either (a) or (b)