The selection of Spiral Model based on characteristics of requirements:
(A) Are requirements easily understandable and defined?
(B) Do we change requirements quite often?
(C) Can we define requirements early in the cycle?
(D) Requirements are indicating a complex to be built

1. A(A) (C) Only
2. B(B) (B) Only
3. C(C) (B) and (D) Only
4. D(D) (A) and (C) Only

Pick an option to check yourself, or open the answer below.